put terminalnotifier in pync package

For #1.

This works fine when you install this in a `virtualenv` using `python setup.py install`. However, when you install it globally using `setup.py`, it doesn't seem to work. That's probably because the while installing globally using `setup.py`, it creates the `egg` file in the same directory and perhaps uses some kind of linking from global `site-packages`. I am not sure. I don't know how exactly `egg` files and `setuptools` handle installation.

But, to install globally for testing, try:
`pip install https://github.com/vaidik/pync/archive/add_terminalnotifier.zip`

This should work. Worked for me.

Also, I have purposely included the version of `terminal-notifier` so that we explicitly make know what version we are using. It would be a good idea to mention that in the `README` as well.