Fix NPC Amy's love hearts crashing if they didn't have a set fuse

See merge request !641

Add missing glseg checks (and remove a superfluous one)

See merge request STJr/SRB2!642

Reorder map loading

See merge request !635

Extra functionality for lua

See merge request STJr/SRB2!601

Fix mouse being grabbed even when not used

See merge request STJr/SRB2!639

The other way around this time.

This reverts commit 6c85c4e1.

Fix usage of V_GetColor

See merge request STJr/SRB2!638

Use GCC 8.1 for AppVeyor 64-bit builds

See merge request STJr/SRB2!624

Add clipboard functionality to the Connect via IP textbox.

See merge request STJr/SRB2!597

I was using V_GetColor in a lot of places I shouldn't have, making the game look wrong with a non-default colour profile.
Though, I left R_RainbowColormap alone.

Remove "z" from "vertex_t"

See merge request !636

Provide a fix for "non-sloped" slopes launch/land behavior by checking the normal's components.

See merge request STJr/SRB2!634

Adapt P_ClosestPointOnLine3D() to be much like FV3_ClosestPointOnLine() and use vector3_t's as args, save for the hypotenuse calculation, which remains the same; the output should be the same as before.
Adapt the rope hang snapping to the new function's form.

Move P_ProcessLinedefsAfterSidedefs into P_LoadMapData, but move map data copying after everything else

Compressing sidedefs can break both special effects and netgame syncing, so let's get rid of it

See merge request STJr/SRB2!628

Textmap parser

See merge request !604

Fix major issue

See merge request STJr/SRB2!625

Remove Direct Draw from AppVeyor config

See merge request STJr/SRB2!622

CV_FindVar for Lua

See merge request STJr/SRB2!583

Do not save netgame-synced console variables

See merge request STJr/SRB2!623

Let the mouse move freely when a menu is open or game is paused

See merge request STJr/SRB2!617

This is a bad thing to do, because if you join a server,
your game will save the host's settings.