Update syntax file for .cabal

[MaskRay]

Incorporate changes in https://github.com/sdiehl/haskell-vim-proto/blob/master/vim/syntax/cabal.vim, notably:

• field names are case-insensitive
• allow whitespace between the field name and the colon

[codecov-io]

Codecov Report

Merging #1777 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1777      +/-   ##
==========================================
- Coverage   75.11%    75.1%   -0.01%     
==========================================
  Files          76       76              
  Lines      124994   125034      +40     
==========================================
+ Hits        93886    93913      +27     
- Misses      31108    31121      +13

Impacted Files	Coverage Δ
src/if_xcmdsrv.c	83.33% <0%> (-2.04%)	⬇️
src/os_unix.c	58.34% <0%> (-0.49%)	⬇️
src/gui.c	45.53% <0%> (-0.11%)	⬇️
src/gui_gtk_x11.c	47.39% <0%> (-0.11%)	⬇️
src/window.c	81.25% <0%> (-0.1%)	⬇️
src/channel.c	83.8% <0%> (ø)	⬆️
src/message.c	68.52% <0%> (+0.05%)	⬆️
src/if_py_both.h	76.01% <0%> (+0.7%)	⬆️
src/gui_beval.c	44.89% <0%> (+0.92%)	⬆️

---

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[chrisbra]

did you contact the maintainer of the file?

[MaskRay]

@Twinside What's your opinion on making this change upstreamed (vim/vim) ?

[chrisbra]

please note, that runtime file changes should be evaluated and processed by their respective maintainer. If they approve the change, they will send an update to Bram for inclusion with Vim. We don't generally process changes here, as long as the runtime file maintainer is not missing.

[coot]

The maintener seems not responding (bump @Twinside), while the changes are really nice to have.

[brammool]

Instead of using ":syn match" with \c in the pattern, use ":syn case ignore" and ":syn keyword". It's a lot faster.

[Twinside]

Yeah go ahead, I don't really have time to track the update to the cabal files

[coot]

If you agree I can become the new maintainer of this file.

[chrisbra]

closin for #2922