Allow transparent parts in translucent FOF and PolyObject planes

See merge request !978

Sync turnobjs for polyrotate_t thinkers in netgames

See merge request !979

Effect 6 flag allows cutting of cyan pixels on FOF and PolyObject planes (even if they're translucent)

Deprecate FixedRem.

See merge request !952

Move drop shadows to the ceiling for objects in reverse gravity

See merge request !973

Clean up some movement code

See merge request !912

Traceback

See merge request !974

Fix waypoint sequence desyncs

See merge request !975

Fix the "Custom skincolors" branch not compiling with GCC 10.

See merge request !966

NOWIPE fixes for colormap and title card wipes

See merge request !962

Add back side wall scrollers & allow using offsets for tagged wall scrollers.

See merge request !955

Possible fix for dedicated server crashes (aka the msvcrt.dll!_mbscat crash)

See merge request !963

Allow input buffer to hold more than 64 tics

See merge request !950

Custom skincolors

See merge request STJr/SRB2!960

Got_AddPlayer: check that I_GetNodeAddress(node) is non-NULL before using strcpy to copy it to the playeraddress array

Fix crumbling floatbob FOFs in MP SS5 rising up into space for no reason

See merge request !961

T_BounceCheese: Fix FOF height desync occurring if the FOF fell down too fast (resulting in a bizarre bouncing back up effect in MP SS5 due to P_FloorzAtPos messing up as a result)

A_SplitShot no target fix

See merge request !956

Lua mapthing len

See merge request !957

A_SplitShot fix: don't even attempt to A_FaceTarget (or anything beyond) if there is no target to face to begin with