1100805 - Fixing consumer group bind and unbind and moving tasks from ta...

...sks/consumer_group.py to consumer group cud manager

https://bugzilla.redhat.com/show_bug.cgi?id=1100805
The variables 'bind_error' and 'bind_errors' are extremely similar. Variable names that are used so close to each other should be avoided. Renaming one here is the recommended solution.