Patch ALE highlights to use dracula colors

By default, they are:

- ALEError => SpellBad => DraculaErrorLine
- ALEWarning => SpellCap => DraculaInfoLine
- ALEInfo => ALEWarning => SpellCap => DraculaInfoLine

- ALEErrorSign => Error => DraculaError
- ALEWarningSign => Todo => DraculaTodo
- ALEInfoSign => ALEWarningSign => Todo => DraculaTodo

Proposed change:

- ALEError => DraculaErrorLine
- ALEWarning => DraculaWarningLine
- ALEInfo => DraculaInfoLine

- ALEErrorSign => DraculaError
- ALEWarningSign => DraculaWarning
- ALEInfoSign => DraculaInfo

after/plugin/dracula.vim

@@ -33,4 +33,16 @@ endif
 
 "}}}
 
+" ALE: {{{
+if exists('g:ale_enabled')
+  hi! link ALEError DraculaErrorLine
+  hi! link ALEWarning DraculaWarningLine
+  hi! link ALEInfo DraculaInfoLine
+
+  hi! link ALEErrorSign DraculaError
+  hi! link ALEWarningSign DraculaWarning
+  hi! link ALEInfoSign DraculaInfo
+endif
+" }}}
+
 " vim: fdm=marker ts=2 sts=2 sw=2: