New CLI command syntax helps

[stroiman]

The muxify CLI now needs a command, two commands exist

• launch - the previous implicit command
• list - lists all projects

This is a breaking change, requiring muxify launch {project-name} instead of muxify {project-name}. Implementing launch as a default command is simple enough, but didn't occur to have any value, as I never call muxify directly, I always use the m script as described in the readme.

Having the list command enables selecting from configured projects straight inside tmux.

bind m display-popup -E 'muxify list | fzf --reverse | xargs m '

This uses prefix+m for muxify as the shortcut. Feel free to change as you see fit.