Added Makefile, Cask and .travis.yml
pyvenv-mode: New mode.

Handles mode line display and automatic virtualenv switches based
on file-local variables.
pyvenv-restart-python: New function.

This function will restart any inferior Python processes. If a
user wants this, they can add it to the post-activate hook.
Support for virtualenvwrapper hooks

We now support running of virtualenvwrapper hooks. This includes
support for importing any environment variables changed by the hook
functions or scripts, by passing the environment from the subshell
back to Emacs.
Add .travis.yml