Tweaks to protected roles in traitor, changeling and vampire

Created by: rmariani

-Security officer and Detective moved out of "protected" for changeling -Security officer and Detective moved out of "protected" for traitor -Security officer and Detective moved out of "restricted" and into "protected" for vampire

This is a cleaning up of an older pr: https://github.com/d3athrow/vgstation13/pull/7756#issuecomment-173437002

People complained about moving sec officer/detective from restricted to unprotected, so I changed that. They will remain restricted, since they are loyalty implanted.

However, I removed Security Officer and Detective as protected jobs from changeling and traitor.

The arguments for them not being completely unprotected for vampire vampire are good and the community wants that, so I merely moved detective and sec officer to protected status from restricted status. I think this is a healthy compromise. This goes in line with entire motivating principle of SS13: it isn't a completely balanced game, and players should always be paranoid. Not being able to rule more roles out as an antag while increase paranoia. (The "protected" designation greatly lowers the chance of a role being the antag in question, while "restricted" completely bars them.)

Much of he reasoning behind protecting or restricting jobs in these rounds is their armory access. Neither detectives nor security officers have armory access. Expanding possibilities for antagonists is a good thing in SS13 to keep the air of paranoia alive, so players can't just rule huge swaths of characters out. Similarly, detective and sec officers don't have power over departments like heads do for cult rounds. If it's safe for HoP, CE or QM to be cultists without a fear of imbalance, these roles will be safer yet, but the greatly lowered frequency creates a good balance between interests.