Group module commands

[Magnus2142]

‘groups’ should contain subcommands:

• list - lists all groups and its members(?) (single groups?)
• get - get a specific group and more detailed information compared to above command
• create - Create a single group or with option to upload members from csv
• delete - Delete a group
• update - update group
• import - use a csv (+ other formats?) to add members to courses, see help in blackboard for format. Also support csv in the same way to add groups
• sign-up/join - Sign up to a group (student command)
• sets (subcommand group)

Make sure to follow the same structure of the commands, options and arguments like in the other modules.