Haskell cleanup.

Make the "compressWhitespace" filter kill \001 characters.
Make the ghc-mod checker use the "compressWhitespace" filter.
Minor formatting of the hlint checker.
Leftover from 7eda5de.  How embarrasing.
Reuse loclists when possible, to allow :lolder and :lnewer.

This is not completely safe: if a loclist is created by something
other than syntastic before the error window is displayed, syntastic
will obliterate it.  There is currently no way to tell if a
loclist was created by syntastic or not.  Undocumented variable
g:syntastic_reuse_loc_lists can be used to disable reuse of loclists.
Bug fix: allow loclist cleanup.
Coffeelint: Fixed errorformat, last line is optional
Merge pull request #765 from AsaAyers/master

Coffeelint: Fixed errorformat, last line is optional
Merge branch 'loclist_count'
Merge branch 'master' into gcc_refactor