* introducing the new friend, SH_FORCEHP (which is used as a bitmask to get the extra hitpoints of a force-shield user)
* P_DamageMobj now considers the unimplemented shield constants as well as the implemented ones.
* When not pressing any direction, you now go backwards by default - to emphasise that this is primarily for defensive, not offensive, purposes.
* The camera can now handle the player going backwards without them going completely off-screen.
* Fixed some overzealous checks.
* The spinfire ring is now capable of damaging enemies. (god, what a terrible hack this is)
* When ground pounding, you now bounce off the floor a little bit to make the ability less spammable.
* The Dodge Dash
* Allows you to dash - no control, no falling, no key response - for 2 + (number of extra shield hitpoints) tics.
* If you're holding movement keys down, you dash in the direction you're holding - otherwise, you dash directly forward.
* You're spinning (spindash spin, not jump spin) until your dash is over, then your momentum is cut down significantly and you end up in falling frames.
* It may not necessarily be super useful for Sonic, but it helps the other characters.
* http://gfycat.com/BogusFailingFritillarybutterfly
* http://gfycat.com/PoliticalIdealisticBallpython (outdated speed, shows any direction)
Animated sky support
What it says on the tin: skies can be animated textures now. Just set them up as normal animated textures (keeping in mind the starting texture still has to comply with the SKYn/SKYnn/SKYnnn naming format) and hey presto, your sky animates.
See merge request !34
* If you hold down your jump button whilst jumping into it, you no longer immediately use your ability.
* Characters with CA_DOUBLEJUMP and CA2_MULTIABILITY no longer lose track of their jump count.
(the problem was that MT_OVERLAY's default radius and height were never getting changed from 1*FRACUNIT, and that meant that when you spindashed, the game considered it completely below the surface of the flat you were standing on. Since you're not usually clipped on flats that don't belong to FOFs, we didn't notice this issue sooner.)
* Camerascale, shieldscale, height and spinheight are now player attributes which are set to the skin attribute on skin change, not read directly from the skin.
* P_GetPlayerHeight and P_GetPlayerSpinHeight are now macros instead of functions.
* Extra protection against switching to a locked skin.
* flips the sprite ala MFE_VERTICALFLIP except you don't need to flip the direction of gravity for the object just to draw upside down
* stacks properly with reverse gravity
HOWEVER, since these changes to PIT_CheckThing do raise questions about whether there may be unintended side effects here. As a result, I may remake this for internal only if necessary.
* Sets the sortscale of the mobj to that of its tracer.
* Basically, Smiles' tails won't clip through shields thanks to this.
* http://gfycat.com/GraveGlassEwe
* Also has support for chains of MF2_LINKDRAW!
