Use `shiftwidth()` instead of `&shiftwidth`

The `shiftwidth` option can be set to 0, in which case the tabstop value
is used instead. In order to always set the correct shiftwidth, the Vim
docs advise the use of the `shiftwidth()` function.
Simplified & extended syntax file

Additions are based in part on Yann Monclair's syntax at
http://www.vim.org/scripts/script.php?script_id=1394
Added several language features to syntax

- matched keyword pairs (begin... end, function... end)
- cleaned up/clarified matched pair operators (brace expansion, variable
  substitution)
- added test regions & operators
- added several errors (syntax used in Bourne-style shells)
Added several language features to syntax

- matched keyword pairs (begin... end, function... end)
- cleaned up/clarified matched pair operators (brace expansion, variable
  substitution)
- added test regions & operators
- added several errors (syntax used in Bourne-style shells)
Merge branch 'master' of github.com:patrick-conley/vim-fish

Conflicts:
	syntax/fish.vim
Highlight arguments to "set", more sh-like colors
Don't highlight numbers in function names
Add an ftplugin for fish profile output files

There's no standard extension for these files, so no ftdetect, but an
ftplugin called `fishprofile` is defined that sets up tabstop and
folding to make it easier to read/navigate these files.

When reading a fish profile file, run `:setf fishprofile` to turn on the
plugin.
Define b:undo_ftplugin and fix b:match_words

Clean up the ftplugin a bit. Use the save_cpo pattern to ensure cpo is
set appropriately, and define a b:undo_ftplugin.

Change the b:match_words definition to match else/else if.
Added several keywords, tokens for invalid syntax
Use fish't test options, add all builtin keywords
Merge branch 'master' of https://github.com/patrick-conley/vim-fish

* 'master' of https://github.com/patrick-conley/vim-fish:
  Use fish't test options, add all builtin keywords
  Added several keywords, tokens for invalid syntax
  Don't highlight numbers in function names
  Highlight arguments to "set", more sh-like colors
  Added several language features to syntax
  Added several language features to syntax
  Simplified & extended syntax file
Merge branch 'shiftwidth-function' of https://github.com/ajaam/vim-fish

* 'shiftwidth-function' of https://github.com/ajaam/vim-fish:
  Use `shiftwidth()` instead of `&shiftwidth`