It's rare that my deps break their api or that newer versions must be avoided,
and very common that they release new versions which I must tediously
and promptly test and release hackage revisions for or risk falling out
of stackage. Trying it this way for a bit.
I dropped these last month, perhaps without meaning to.
They probably should stay. hledger-ui (eg) will still build
with minor updates of hledger-lib or hledger, but will require
either a release or a hackage revision to build with a major
update.
hledger-lib had a valid install plan with GHC 7.8, but requires GHC 7.10 to compile (currently).
Require base 4.8+ everywhere so that stack/cabal will enforce a supported GHC version early.
Also, bump hledger-ui's "stability" to "stable".
Generated package.yaml files from the old cabal files with hpack-convert,
removed some problematic blank lines manually,
regenerated the cabal files from the package.yaml files with hpack.
Tests pass, looks like all the info is still there.
This means that from now on, we don't edit cabal files directly.
We edit the less verbose package.yaml files. stack will update
the cabal files automatically (or non-stack users can use hpack).
The changes to both are committed, as we still want to provide
the cabal files to downloaders.
