Pipe fixes

- Cleans up silent pipe deleting (now creates a loose pipe item where the pipe section was)
- Allows pipe painters to paint disconnected pipes
- Removes OOC message from IC feedback
Atmos Overhaul - Phase 1

- Implements omni device core framework
- Adds omni gas mixer
Added omni filters

- Added omni gas filter
- Cleaned up some code in mixer.dm and omni_base.dm
Add omni devices to dispenser

- Added omni filters and mixers to pipe dispenser
- Added construction code
- A couple more cosmetic tweaks
Uncommented gateway spawn point.
Fixes multiple runtimes in mutiny mode.

Example runtime:

runtime error: Cannot read null.assigned_role
proc name: get crew to terminate (/datum/directive/terminations/financial_crisis/get_crew_to_terminate)
  source file: financial_crisis_directive.dm,11
  usr: null
  src: /datum/directive/terminations/... (/datum/directive/terminations/financial_crisis)
  call stack:
/datum/directive/terminations/... (/datum/directive/terminations/financial_crisis): get crew to terminate()
/datum/directive/terminations/... (/datum/directive/terminations/financial_crisis): meets prerequisites()
mutiny (/datum/game_mode/mutiny): get directive candidates()
mutiny (/datum/game_mode/mutiny): pre setup()
/datum/controller/gameticker (/datum/controller/gameticker): setup()
/datum/controller/gameticker (/datum/controller/gameticker): pregame()
/datum/controller/game_control... (/datum/controller/game_controller): setup()
Stole a bunch of Vox clothing icons from /vg/.
More icon changes, updates item paths, moves vox cortical stack spawn to raider proc, makes vox whitelisted and spawnable with internals.
Omni device tweaks

- Better mapping support (mapping icons and can now set mixer concentration)
- Trimmed overlay lists
- Utilized existing procs for icon generation
- Changed filter icon color to better contrast the output color
Mapper sanity checks

- Checks that mapped values add up to 100% so mappers can't set unusual ratios
Bug fix and mapping example

- Fixed mapped omni devices being set to off at round start
- Remapped the research outpost atmos room, taking advantage of omni devices
Improves shuttle ETA calculation
Fixes shuttles getting stuck if the docking...

...controller they are trying to dock with has been destroyed or is not
responding.
Fixes base shuttle console requiring engine access
Updates secrets panel to use the new shuttle...

...datum correctly.
Merge pull request #5366 from alex-gh/mutiny_runtime_fix

Fixes multiple runtimes in mutiny mode.
Merge pull request #5368 from Zuhayr/dev

Uncommented gateway spawn point.
Fixes ERT shuttle not announcing a cancelled...

...launch if the launch is cancelled after the countdown is completed.
Merge remote-tracking branch 'remotes/upstream/dev' into atmomerge
Improves the fix for shuttles being stuck if...

... the docking controller is destroyed.