Summon Security Function added to Command and Security PDAs

![message](https://cloud.githubusercontent.com/assets/3828067/4350410/472e2794-41e8-11e4-8bc5-22a354700434.png)

- Attached to Command and Security PDA cartridges
- Broadcasts a message to all SecHUDs
- Cannot be used while PDA is under effects of EMP
- Requires an active messaging server to use
- Optionally, a reason may also be attached to the summons

Intended to help bridge the gap between Heads and Security without giving heads full security radio access.