Allow functions to be declared as error handlers
Fix comment syntax for highlighting
Add ErrorHandler Binary instance
Proper checking for language extension
Merge remote-tracking branch 'origin/error-reflection' into error-reflection
Allow querying the registered error handlers
Check the type of elaborated error handlers
Add Eq instance for Either
catch exception thrown by tryLoadLib on Windows

`tryLoadLib` uses `loadLibrary` to load DLL on Windows, which throws
`IOException` upon failure such as file not found. Currently we only
checks whether the return value is `nullPtr` or not.

This commit adds a handler that tries to catch the `IOException` thrown
by `loadLibrary` and returns `nullPtr` instead.
Add tab completion for "induction" in prover
Allow functions to be declared as error handlers
Fix comment syntax for highlighting
Add ErrorHandler Binary instance
Proper checking for language extension
Allow querying the registered error handlers
Check the type of elaborated error handlers
Merge remote-tracking branch 'origin/error-reflection' into error-reflection
Merge pull request #772 from david-christiansen/either-eq

Add Eq instance for Either
Merge pull request #773 from suhorng/fix/master/catch-windows-tryloadlib-exception

Catch exceptions thrown by tryLoadLib (on Windows)
Merge pull request #774 from david-christiansen/induction-completion

Add tab completion for "induction" in prover