Make the README a little prettier (haskell/ghcide#1949)

* Make the README a little prettier

* Remove vscode.png

* Image float right

* Go back to regular title; scale image 75%

ghcide/README.md

@@ -1,7 +1,10 @@
-# `hie-core` (Haskell IDE Core)
+# `hie-core` (Haskell IDE engine)
 
 Our vision is that you should build an IDE by combining:
 
+
+<img style="float:right;" src="img/vscode2.png"/>
+
 * [`hie-bios`](https://github.com/mpickering/hie-bios) for determining where your files are, what are their dependencies, what extensions are enabled and so on;
 * `hie-core` (i.e. this library) for defining how to type check, when to type check, and producing diagnostic messages;
 * A bunch of plugins that haven't yet been written, e.g. [`hie-hlint`](https://github.com/ndmitchell/hlint) and [`hie-ormolu`](https://github.com/tweag/ormolu), to choose which features you want;
@@ -46,7 +49,7 @@ Once you have got `hie-core` working outside the editor, the next step is to pic
 
 ### Using with VS Code
 
-Install the VS code extension
+Install the VS code extension (see https://code.visualstudio.com/docs/setup/mac for details on adding `code` to your `$PATH`):
 
 1. `cd compiler/hie-core/extension`
 2. `npm ci`