1 new theme + change to git.plugin.zsh

Changed git.plugin.zsh > added an in_git function to check if user is in a git repo. 

Added a netpunk.zsh-theme … displays battery charge remaining using batcharge.py (ripped it out from some theme, don't remember which), date, ruby version via rbenv (i'll do rvm soon, because most of the guys and girls at work use rvm)... And it points out werther you're in a GIT or HG repository (in nice friendly letters), has improved HG functions, but requires hg plugins prompt, tasks and mq. 

Will you pull it?