Move install functionality to rcm hooks
zsh: use .cache/zsh instead of .zsh/cache
zsh: Use system version of fasd
zsh: Create dotfile links under $ZDOTDIR

For some reason, zsh expects files under $ZDOTDIR to be dotfiles, unlike
many other programs.
zsh: Use (and set) XDG_CONFIG_HOME for $ZDOTDIR
zsh: Use $ZDOTDIR instead of hardcoded path
Rename launchagents folder
Add rcrc file for excludes
rcrc: test and source rcrc.local