FoD: Allow users and/or groups to be given access to applications

[kadraman]

Update the 'fcli fod add' and 'fcli fod update' commands to allow users and groups to be given/revoked access to applications Examples include:

fcli fod update MyApp --add-user XXX --add-user YYY --add-group AAA --add-group BBB
fcli fod update MyApp --delete-user XXX --delete-group AAA

[kadraman]

Initially this will be done on the users and/or users-groups. It may be worth adding onto the application as well but this is duplication?

[rsenden]

Also see #369 for general discussion on this topic.

[rsenden]

We do already have support for assigning users to groups & applications, and assigning groups to users and applications, through the fcli fod access-control update-user and fcli fod access-control update-group commands. Do we need any other functionality, and/or revisit current implementation?

[kadraman]

I think existing functionality at access-control level is OK for now - will keep it as low priority unless a customer specifically requests it.