Fire alarm fixes

* Fixes fire alarm not showing blinking red light when activated. Fixes #4382
* Fixes security level light on fire alarm to be off when alarm is off/broken/missing components.
* Fire alarms in the same area now all blink red if one alarm in the area is activated, not just the specific alarm who was activated.
* Disassembling a broken fire alarm doesn't drop a circuit now, you "remove the destroyed circuit."
* Reducing the number of icon_states used, using overlays for all fire alarm lights. Fixing sprite inconsistency (fire alarm_frame's red border is no longer brighter than unpowered fire alarm's border)
* Gives the blue alert light a brighter color for better visibility.

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From left to right and top to bottom: green, blue, red alert ; no power ; activated and green, blue, red alert ; 
open panel ; open panel and no power ; wires removed ; circuit removed.