Added assertion to LoggedUserDetails test cases
Updated init state template. There is now a field where the tester can
input the ID of the group that contains their test accounts. This is
useful for the several operations that are related to groups.
Updated GetGroup test cases to use a group specifically chosen by the
user instead of searching for one and relying on Facebook's state. Added
a helper method to retrieve the ID specified by the tester in the
properties file.
Updated GetGroupMembers test cases