Add travis configuration file for continuous integration
Include pypi and travis-ci badges on README.rst
Define travis install and test directives
Add a unit test for non-existent package directories

If a package is defined in .dotfilesrc and the package directory doesn't exist
in the repository when you attempt to add it, an IOError exception is thrown.
This test captures the failing scenario.

In reference to #17.
Create non-existent package directories

Closes #17.
Add documentation unsync operation