Trailing slash

* made haruploader tolerate url's with a trailing slash
* unit tests for above
* editied test_config.yaml and changed url's to a single URL pointed at example.com, so the acceptance test runs faster and doesn't access edx.org.

/cc @clytwynec @benpatterson @jzoldak  
Yea.  I'd say mark this with a `TODO: Refactor haruploader to make this testable in context` along with adding a backlog ticket, so that we don't lose track of it.