Allow migration of users with CCMA without groups

Problem Definition

When we choose to migrate only users related to selected spaces, the groups are migrated too

Suggested Solution

It would be nice to have extra option (like JCMA) to migrate only users without groups. eg:

• Only users referenced in spaces
• Users and groups referenced in spaces
• Include any user that is a member of a group in this migration

Why this is important

• Decision to manage groups in a different ways on Cloud, hence would like to start new group names on Cloud
• When migrating groups, CCMA migrated all group members too which could be out-of-scope users

Workaround

• Manually cleanup the groups before the migration

Currently CCMA has 2 options for User migration

• Migrate All Users and Groups
• Migrate Users and Groups related to selected spaces (There is a mis-nomer here being tracked by MIG-1270: Migrating "Users related to selected space" Migrates groups too  )

As there is already a feature 

MIG-664: Option in CCMA to migrate Spaces only without any user data to allow skipping of users altogether. 

This feature request has been opened to allow only "Users" to be migrated and have the ability to skip groups.