GitLab

- simple theme
- hostname and current folder on left prompt
- git branch and working tree status on the right

The ll alias is a very common default for bash in Linux distributions, so use
that definition.

This is useful when you want to use a dangerous command, as it won't be
available with history searching.

It breaks "ebuild <foo> manifest", as there are Manifest files in the directory.

Initial implementation of a new plugin system, so that people can managed which aliases/functions they want.

adding my zsh theme -- only difference from robby's being that i'm using white instead of blue for legibility over brown