Add missing pragmas

Add the new or missing pragmas `INLINABLE`, `MINIMAL`, and `NOUNPACK` to
the omnicompleter. Also sort the list and put each item on its own line
to improve future diffs.
Fix typo in document

Thanks @itchyny (#34)
`ghc-mod browse` could return an empty string (#34)

However, I think it's a ghc-mod's bug.
ghc-mod now requires the 'version' command to print the version (as of https://github.com/kazu-yamamoto/ghc-mod/commit/5a4bec87559d2a6ea3db5c3ca516ab68f8c10387)
Merge pull request #39 from ajnsit/master

ghc-mod now requires the 'version' command to print the version
Merge pull request #31 from ianbollinger/add-pragmas

Add new GHC pragmas to omnicompleter
Fix #41 necoghc#ghc_mod_version() parse
Fix #41 version check string