Configurator tests

Fairly large overhaul of Apache configurator in order to allow for unittesting.  The unittests aren't complete, but this includes a fair start.  I would like to get this merged with master so that everyone can work with the same code.  I will then continue to go for 100% unittest code coverage for the configurators.

I believe I only added one new public function (get_version()) which does contain a unittest.

All of the unittests pass, my demo integration tests pass and I have removed all pylint errors.

Comments are welcome.
I was attempting to rid the project of any pylint -E errors.
http://stackoverflow.com/questions/6336882/pylint-doesnt-like-pkg-resources-resource-filename
************* Module letsencrypt.client.acme
E: 12,28: Module 'pkg_resources' has no 'resource_filename' member (no-member)