Got the sample to work with the MergedClient
* Changed client in use_client.py to use two MergedClients
        - there is now an alias_client and user_client
* Changed tests so they consistently use client_id instead of clientid
        - all tests are now passing except for email, policies and group list tests
* Cleaned up policy and GoAuth tests a little
* Changed MergedClient constructor so it uses a config file for all values
* Added goauth prefix to goauth functions
* Removed go_host form merged_client
        - all calls to self.go_host now use self.server from the config file
* Removed client.py and go_rest_client.py in lib/nexus
* Removed lib/tests directory
        - all tests are in lib/merged_tests now