Add syntax and filetype plugins for SWIG (Simplified Wrapper Interface
Generator) description files.

The default syntax for .i files highlights comments in a reverse
color scheme which doesn't look well.  This syntax builds
on vim's c++ syntax by adding highlighting for common swig
directives and user defined directives.  For an alternative
syntax, see vimscript vim/vim#1247 (which I found after writing this).

closes: vim/vim#13562

https://github.com/vim/vim/commit/2e31065a650015892179e520038bf2083a9519b6

Co-authored-by: Julien Marrec <julien.marrec@gmail.com>
Co-authored-by: Matěj Cepl <mcepl@cepl.eu>

runtime(script.vim): make strace ft check less strict (vim/vim#13482)

Strace output, depending on parameters (-ttf this time), can dump both
times and pid:
  1038  07:14:20.959262 execve("./e.py", ["./e.py"], 0x7ffca1422840 /* 51 vars */) = 0 <0.000150>

So loose the regexp matching this, so that the above is matched too.

Fixes vim/vim#13481.

https://github.com/vim/vim/commit/2f54c13292af053ec00c18e5fded87b1bc602822

Co-authored-by: Jiri Slaby <jirislaby@gmail.com>
Co-authored-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>

Problem:  Not all Dart files detected
Solution: Add shebang filetype detection for Dart

closes: vim/vim#13449

https://github.com/vim/vim/commit/c1c177a47bfe1b9a524ede2743a689e461668d14

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:  Janet files are not recognised
Solution: Add filename and shebang detection (without
          adding an extra filetype plugin)

Those are used by the Janet language:
http://www.janet-lang.org

closes: vim/vim#13400

https://github.com/vim/vim/commit/c038427d2a27445e612761f19c92b2b8b05afdea

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:  Rexx files may not be recognised
Solution: Add shebang detection and improve disambiguation of *.cls
	  files

closes: vim/vim#12951

https://github.com/vim/vim/commit/e06afb7860805537ccd69966bc03169852c9b378

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:  Vimball/Visual Basic filetype detection conflict
Solution: runtime(vb): Improve Vimball and Visual Basic detection logic

Only run Vimball Archiver's BufEnter autocommand on Vimball archives.
Fixes vim/vim#2694.

closes: vim/vim#12899

https://github.com/vim/vim/commit/f97f6bbf56408c0c97b4ddbe81fba858d7455b0d

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:  runtime: crystal scripts not recognised
Solution: Filetype detect Crystal scripts by shebang line

closes: vim/vim#12935

https://github.com/vim/vim/commit/9b73902dbe6f7940326bcd8dbc89d010d85d69c5

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:  cannot distinguish Forth and Fortran *.f files
Solution: Add Filetype detection Code

Also add *.4th as a Forth filetype

closes: vim/vim#12251

https://github.com/vim/vim/commit/19a3bc3addf9b4aa8150a01b11b4249c67d15d3b

Don't remove filetype files from Vim patches:
- filetype.vim, script.vim, ft.vim usually contain useful changes
- script.vim and ft.vim don't even have their paths spelled correctly

Co-authored-by: Doug Kearns <dougkearns@gmail.com>

Problem:    Nix files are not recognized from the hashbang line.
Solution:   Add a hashbang check. (issue vim/vim#12507)

https://github.com/vim/vim/commit/19548c6a742d954ecd0b50b0680c37cc6ced7473

Co-authored-by: Bram Moolenaar <Bram@vim.org>