New assertion was added to GroupCreationTests

New assertion was added to GroupCreationTest class. This assertion
compare size of list of group before and after group creation. New
method getGroups also added to GroupHelper class.
Group list comparison modified in GroupCreationTests

Group list comparison modified in GroupCreationTests. Size checking is
replaxed by group names checking. Additional method for comparison was
added to GroupData.
New check was added to AlsOfGroupCreationTests

New check was added to AlsOfGroupCreationTests. Now List of groups
before and after group creation are compared.
New check was added to GroupRemoval and GroupModification tests

New check was added to GroupRemoval and GroupModification tests. Group
lists before and after removing/modification are compared.