Add an option to make Activity Codes invisible to agents.

We'd like to have the option to make individual Activity Codes visible or invisible to different access levels.

For example, we currently have separate out-of-office Activity Codes for approved time off and unapproved time off. When agents are viewing their co-workers' schedules in WFM, we don't want them to be able to see the Activity Codes for unapproved time off.

Ideally, this would be a permission setting on each new code created. Admin would have the ability to view/select all Activity Codes regardless of whether the code was toggled to "invisible." All other access levels would be subject to the selected permissions.