Use srp.add_srpfleetmain

This allows for users with the srp.add_srpfleetmain permission to create new SRP fleets.

Before only those with the srp_management permission could add SRP fleets. This is much better than all or nothing.

Also adds a new @permissions_required decorator to allianceauth.authentication which does exactly what the base @permission_required does, but takes a tuple and will return true if the user has any of the permissions listed, rather than requiring the user to have all of the listed permissions.