fixed unpushed git changes in prompt
better emacs server detection
prompt gracefully degrates to two lines with lots of crap

When there's a virtualenv and git info, the prompt gets crowded. this
degrades it gracefully to a 2-line prompt, but tries to keep it one
line when possible.
add emacs sh-scratch buffer
C-c v to set virtualenv in emacs
pychecker passes pychecker....
install dependencies in postactivate, not postmkvirtualenv