Finding nested groups queries each single group separately

If nested groups are enabled, when we recursively search for groups a user/group is in, we iterate groups at each level one by one, searching for its parents. Instead, we should query multiple groups at one (with some limit, to avoid blowing up DB with a huge query).

See

1. com.atlassian.crowd.manager.directory.RemoteDirectorySearcher#findNestedGroupMembershipsIncludingGroups
2. com.atlassian.crowd.manager.directory.RemoteDirectorySearcher#isUserIndirectGroupMember