Cleanup and remove browser code.

This pulls many of the capybara changes from the base class in by not reimplementing those methods in our browser class.

I was able to remove many methods and just implement a similar interface as the base class by adding 3 new methods in.  All tests pass.

I also contend that the functionality added in #32 should not be supported.  I can't find anyone else adding paths into capybara's app_host.  It seems after looking at capybara's code (and our own) that the app_host should only ever have the host in it.  I've removed the functionality and some of the related tests.