Movement with wheelchair not possible in space

(cherry picked from commit a80f2b12e68d24749a7344af59a759d503dc4b74)
Minor code cleanup

(cherry picked from commit 164bf1516657c7cbd6b5c29286b640828b03613d)

Conflicts:
	code/modules/mob/mob_movement.dm
Fixes. Wheelchair is supposed to help the occupant and not the driver, damn it.

(cherry picked from commit 3c1d0a83bf45b2e420c9cdf4e0bb2c7fb1e3b9ab)
Fixes wrong person getting movement penalty

(cherry picked from commit 4981f3409fcdf1ad08370143064ddc60d5416ea3)
Fixes non-existant feet getting bloodied and adds blood to wheelchairs

(cherry picked from commit c0ae74b813d98596542a9f21343c5a4178bade7c)
Wheelchairs spawn on footless characters

(cherry picked from commit 1e09995f63c43633555bed805545f3be6ded9d61)

Conflicts:
	code/modules/client/preferences.dm
Fixes canmove updating wrongly on movable chairs

(cherry picked from commit 6568533d0daa405ff18769928464d32f02fe53d7)
Cleans code up for easier editing

(cherry picked from commit a6e6a8939ff3e9a213477a3e309373327d7a3d4e)
helpers: fix move_contents_to() not moving air

fixes #5232

Signed-off-by: Mloc-Argent <colmohici@gmail.com>
(cherry picked from commit 38c5b380172cf362fb6e55185c177b688442326a)
Фикс дюпа в фабрикаторе мехов
Merge branch 'base' into _beta