Removed syntastic and replaced it with ale

Read more here:
https://github.com/w0rp/ale

sources_non_forked/ale/ale_linters/haskell/hlint.vim

@@ -0,0 +1,34 @@
+" Author: jparoz <jesse.paroz@gmail.com>
+" Description: hlint for Haskell files
+
+function! ale_linters#haskell#hlint#Handle(buffer, lines) abort
+    let l:output = []
+
+    for l:error in ale#util#FuzzyJSONDecode(a:lines, [])
+        if l:error.severity is# 'Error'
+            let l:type = 'E'
+        elseif l:error.severity is# 'Suggestion'
+            let l:type = 'I'
+        else
+            let l:type = 'W'
+        endif
+
+        call add(l:output, {
+        \   'lnum': str2nr(l:error.startLine),
+        \   'col': str2nr(l:error.startColumn),
+        \   'end_lnum': str2nr(l:error.endLine),
+        \   'end_col': str2nr(l:error.endColumn),
+        \   'text': l:error.severity . ': ' . l:error.hint . '. Found: ' . l:error.from . ' Why not: ' . l:error.to,
+        \   'type': l:type,
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('haskell', {
+\   'name': 'hlint',
+\   'executable': 'hlint',
+\   'command': 'hlint --color=never --json -',
+\   'callback': 'ale_linters#haskell#hlint#Handle',
+\})