MF2_LINKDRAW reliability improvements
Seriously improves the reliability of the linkdraw system (in Software, the only rendering engine which actually does anything with this information), reducing the number of visual errors it produces significantly. Deliberately engineered to only affect objects with MF2_LINKDRAW applied.
Of particular note: Standing in shallow pools of water as Smiles will now reliably associate the bottom half of the tails following mobj with the underwater portion of Smiles' body, and the flicking ends with his un-submerged head.
Test with ```<root>/!LatestSRB2Files/srb2win_branch_linkdraw.exe``` and ```<root>/toaster/smiles.wad```.
See merge request !101
Wallspike tweaks
Sorry, MI. You told me to test the objects via objectplace, and they worked fine there - but @FuriousFox had some [issues](http://i.imgur.com/DQuLYzz.png) when he finally got to place them via mapthing.
Specifically, I think the problem this was caused by was a straight up copypaste of the "height" attribute of MT_SPIKE into the "radius" field of MT_WALLSPIKE, when it should technically be half that to match the intended collision box. Some other stuff also got adjusted to match when I solved this.
FF's happy now - they work well enough to place, even if their [collision is a little wonky](http://i.imgur.com/o2rG0tV.gifv), but that's an MF_PAPERCOLLISION issue and more than a quick fix to be done in an evening.
Nab ```<root>/!LatestSRB2Files/srb2win_branch_spikefix.exe``` to test.
UPDATE:
* Support for MF_PAPERCOLLISION tmhitthing in P_SlideMove.
* Knockback for wallspikes is much more consistent, fixing FF's gif as posted above/below.
* Optimised away a FixedDiv call when determining the slopetype of a line.
* Changed the position of the wallspike base slightly.
* Made it so NOTHING can step up onto the player outside of other players, essentially killing a bunch of springs-launch-with-players style bugs. (I was able to recreate that issue with the wallspikes until I added this, which is why I did it in this branch.)
* Wallspikes are now bustable.
* Invert the solidity mapthing flag for spikes and wallspikes.
* Improve the frame arrangement for vertical spikes' spriteset. (Requires new patch.dta)
* Make all spikes consistently do damage with DMG_SPIKE.
* (unrelated) renamed "flame stomp" to "elemental stomp" in P_HitDeathMessages.
* (unrelated) Make gas jets not make noise if they have the ambush flag, per Sphere's request.
See merge request !107
This allows saving in special cases where you can go to a map that
doesn't save, and then back to the map you saved on (see: SUBARASHII
special stages), while still preventing you from killing your lives by
repeatedly retrying in said map.
Kept lastmapsaved just in case. Can be removed if deemed unnecessary.
* Fix an issue where everyone being game overed except for one person, and then kicking that one person, meant the game over trigger was never met.
* Fix an issue where the spectator text could be overridden with a count of the number of remaining players to complete the level.
* Fixed a few glitches with spinning. (Unrelated to the branch, but exposed through new_coop testing.)
* If NONET, the Multiplayer option on the main menu leads directly to the Splitscreen menu, which also includes player 1/2 setup under this circumstance.
* A mechanism to save player name, skin and colour as defaults to config.cfg.
* Improve the code for busting vertical spikes.
* Improve the frame arrangement for vertical spikes' spriteset. (Requires new patch.dta)
* Make all spikes consistently do damage with DMG_SPIKE.
* (unrelated) renamed "flame stomp" to "elemental stomp" in P_HitDeathMessages
* Support for MF_PAPERCOLLISION tmhitthing in P_SlideMove.
* Knockback for wallspikes is much more consistent.
* Optimised away a FixedDiv call when determining the slopetype of a line.
* Changed the position of the wallspike base slightly.
* Made it so NOTHING can step up onto the player outside of other players, essentially killing a bunch of springs-launch-with-players style bugs. (I was able to recreate that issue with the wallspikes until I added this, which is why I did it in this branch.)
Or rather, I killed anything to do with the old background orb, renamed all "EMMY" stuff to "TOKEN", and of course adjusted the new S_TOKEN accordingly
