WebAdmin improvement

[atarkowska]

• Users will still need to be in a group, so the admin will need to create a group before they create users. If admin tries to create users and there are no groups (except users and system) then there is a clear messages that says something like "Users must be in a group - You have not created any groups. Click here to create a group".
• Admins should be able to login to any group (and browse data) regardless of whether they are a member or not.
• The UI should reflect the database: Only fields that are not-null in the database should be 'required' at the UI.
• Would be nice if the 'Active' check-box for in the user-creation form was checked by default. I have often created new users and missed the 'Active' check-box.
• Would be nice to only select a user's 'default' group from groups that they are in, instead of choosing from all groups (same as in the other clients when you switch default group).
• Prefer not to list "system" as one of the available groups for adding users to. Instead have a "Make this user an Admin" option. Otherwise it's not clear what 'system' is.