LLLMS-31: Create new Moodle L3 enrollment plugin

This commit is a large refactoring of the getUDSPerson and CHUB API's.  I've moved to autoloading and namespaces to clean up the code and to allow us to write unit tests which mock those services.

Task-Url: https://jira.doit.wisc.edu/jira/browse/LLLMS-31