link and excerpt what announcements I can find

Release announcements sometimes include a brief summary, which is also
useful here.  Some of these announcement links could be improved by
linking them in the context of the hledger rather than ledger
list. There may be more more that gmane search didn't find.

doc/site/release-notes.md

@@ -63,6 +63,10 @@ change logs.
 
 ## 2014/5/1 hledger 0.23
 
+*This release includes command-line fixes and polish, a new accounts
+command, and a number of changes to the balance command relating
+to --depth, --flat, and multicolumn mode, which I find has made it much
+more useful. --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/1028)
 
 Changes since 0.22.2:
@@ -214,6 +218,8 @@ Improved:
 
 ## 2013/12/13 hledger 0.22
 
+[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/5333)
+
 **New:**
 
 - balance: with a reporting interval (monthly, yearly etc.), the
@@ -434,6 +440,9 @@ Marko Kocić, Max Bolingbroke, and a big welcome to first-time committer John Wi
 
 ## 2012/10/21 hledger 0.19
 
+*This release has just two visible changes: a much faster balance command, and support for the latest GHC and libs. --*
+[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/4190)
+
   * hledger, hledger-lib: support GHC 7.6 and latest cmdargs, haskeline, split
   * balance report no longer has an O(n^2) slowdown with large numbers of accounts,
     and is generally more speedy. Benchmark on a 2010 macbook:
@@ -470,6 +479,8 @@ Marko Kocić, Max Bolingbroke, and a big welcome to first-time committer John Wi
 
 ## 2012/5/29 hledger 0.18
 
+[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/3736)
+
   * web: hledger-web is now based on yesod 1.0
   * web: fix js error breaking second use of add form ([#72](http://bugs.hledger.org/72))
   * web: make `yesod devel` work
@@ -489,6 +500,9 @@ Marko Kocić, Max Bolingbroke, and a big welcome to first-time committer John Wi
 
 ## 2012/2/1 hledger 0.17
 
+*This release mainly fixes bugs and updates dependencies --*
+[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/3149)
+
   * support HP 2011.4.0.0
   * support and require cmdargs 0.9
   * allow non-threaded builds, supporting more debian architectures
@@ -527,6 +541,8 @@ Marko Kocić, Max Bolingbroke, and a big welcome to first-time committer John Wi
 
 ## 2011/10/1 hledger 0.16
 
+*This is a stability/bugfix/polish release (which may become the pattern for
+even-numbered releases in future.) --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/521)
 
   * cli: strip the -- when calling add-on commands, so their options work (#64)
@@ -564,15 +580,13 @@ Marko Kocić, Max Bolingbroke, and a big welcome to first-time committer John Wi
 
 ## 2011/9/2 hledger 0.15.1, hledger-web 0.15.2
 
-[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/479)
-
   * fix a parsec 2 incompatibility
   * web: add missing Hledger.Web.Options to cabal file
   * web: tighten up dependencies to reduce build problems
 
 ## 2011/9/1 hledger 0.15
 
-[announcement](https://groups.google.com/forum/#!topic/hledger/-WCfnRFVaf0/discussion)
+[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/2748)
 
   * hledger's options are now modal, providing better help (using cmdargs)
   * hledger now lists and runs any hledger-* add-ons found in the user's path
@@ -645,6 +659,9 @@ Stats:
 
 ## 2010/12/6 hledger 0.13
 
+*readline editing and tab completion
+from Judah Jacobson, more ledger compatibility, a more robust and
+installable web interface, bugfixes, and a much-deliberated package split. --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/296)
 
   * move web, vty, chart commands into separate hledger-web, hledger-vty,
@@ -756,6 +773,7 @@ lines of code with 132 tests and 54% unit test coverage.
 
 ## 2010/05/23 hledger 0.10
 
+*installation and bug fixes and api improvements --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/242)
 
   * fix too-loose testpack dependency, missing safe dependency
@@ -788,6 +806,8 @@ code including tests, 144 tests, 53% coverage.
 
 ## 2010/04/10 hledger 0.9
 
+*many bugfixes and small improvements, GHC 6.12 support, and a separate library package
+to make building (h)ledger-compatible tools easier. --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/239)
 
   * ghc 6.12 support
@@ -840,6 +860,7 @@ at 3983 lines of non-test code, 139 tests, 53% coverage.
 
 ## 2010/02/11 hledger 0.8
 
+*Bug fixes, refactoring and Hi-Res Graphical Charts. --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/210)
 
   * parsing: in date=date2, use first date's year as a default for
@@ -914,13 +935,12 @@ at 3377 lines of non-test code, 97 tests, 53% test coverage.
 
 ## 2009/06/22 hledger 0.6.1
 
-[announcement](http://thread.gmane.org/gmane.comp.finance.ledger.hledger/156)
-
   * avoid use of exitSuccess which was breaking ghc 6.8/base 3
     compatibility (issue \#2)
 
 ## 2009/06/13 hledger 0.6
 
+*Some pre-built binaries are now available. cabal install ... works on gnu/linux, mac and windows. Hurrah! --*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/1215)
 
   * now cabal-installable on unix, mac, and windows, with Haskell
@@ -1007,6 +1027,13 @@ Release stats:
 
 ## 2009/04/03 hledger 0.4
 
+*There is also a new website at http://hledger.org, with screenshots (textual!),
+a demo (will it survive!?), and docs (not too many!)
+...
+I wrote it because I did not want to hack on c++ and because haskell seemed a good fit.
+...
+Install with the "-f happs" flag to enable the new happstack-based web interface.
+--*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/1097)
 
   * new "web" command serves reports in a web browser (install with
@@ -1141,6 +1168,18 @@ Release stats:
 
 ## 2008/10/15 hledger 0.1
 
+*I'm pleased to announce the first release of hledger, a command-line
+accounting tool similar to John Wiegley's c++ ledger. hledger generates
+simple ledger-compatible transaction & account balance reports from a
+plain text ledger file. It's simple to use, at least for techies.
+
+This has been my "learning Haskell" project, but I think it's also
+useful. It is much less featureful than ledger, and not quite as fast,
+but it has the virtue of being fun for haskellers to hack on. I am
+documenting the code, the app is simple, and I'm not too far up the
+haskell learning curve, so I think other people learning haskell might
+enjoy a look. It is currently ~1100 lines of haskell excluding tests.
+--*
 [announcement](http://thread.gmane.org/gmane.comp.finance.ledger.general/775)
 
 Release stats: