Added tcsh completion

[Br1ght0ne]

• [X] short options (-l, -r, ...)
• [X] long options with parameters (--mode=, --steps-per-sec=, ...)
• [X] long options without parameters (--help, --version)
• [X] mode name completion (default, dense) for --mode=
• [X] color name completion for short options (-c, -C)
• [X] color name completion for long options (--background, --color)
• [X] completion stops after --help and --version
• [X] completion doesn't complete anything besides options (like filenames)
• [X] comment guiding on manual installation

I'm not well-versed in tcsh, but this should suffice for now. If somebody with an experience in tcsh completions, it can be changed later.

Related to #5.

[M4444]

Heh, you seem to really like these completion scripts :D Hopefully I can get to review this soon but in the meantime you can add a licence header and tabs.

[Br1ght0ne]

Thank you!

We should probably consider adopting an .editorconfig for the project...

[M4444]

How did you test the script without knowing the path?

[Br1ght0ne]

$ tcsh
$ cd completions
$ source tmatrix-completion.csh

[Br1ght0ne]

When one - is typed it should also complete suggest completions for with --.

This is not easy with tcsh for two reasons:

• tcsh doesn't give you a list of possible completions on double-tapping Tab, like bash and zsh do, so it really does only word completion
• the suffix (space is the default, = for long options) needs to be specified explicitly for each completion set, so we can't do short and long options at the same time.

First point is the key here: tcsh won't help you to find arguments through a list of possibilities, it just helps you to type the argument you already knew faster.

Surely, I could do something like adding -- to tmatrix_short_options, but it would change nothing in tcsh's behaviour with these completions loaded.

[Br1ght0ne]

There seems to be no "default" path for tcsh completions. Users are supposed to put their completions wherever they fancy and source them in ~/.tcshrc.

Here's an excerpt from git-completion.tcsh:

# To use this completion script:
#
#    0) You need tcsh 6.16.00 or newer.
#    1) Copy both this file and the bash completion script to ${HOME}.
#       You _must_ use the name ${HOME}/.git-completion.bash for the
#       bash script.
#       (e.g. ~/.git-completion.tcsh and ~/.git-completion.bash).
#    2) Add the following line to your .tcshrc/.cshrc:
#        source ~/.git-completion.tcsh

So we can do something like ${HOME}/.tmatrix-completion.tcsh and instruct users to source it by themselves.

[M4444]

In that case we can do it in a similar way, just adding a comment instead of CMake commands. I think the 0th point can be dropped because it's not that important and their tcsh completion seems to be tied to the bash completion so that can also be cleared out.

[M4444]

Thanks for the contribution :)