Update window caption when ending game
Fix DOOM2.WAD saves being put in NERVE.WAD folder

If NERVE.WAD is loaded, nerve bool is true.
Don't open menu on titlescreen when ALT+ENTER/TAB
Determine desktop width and height correctly

If starting in windowed mode, desktopwidth and desktopheight weren't
being set, causing problems when using them in SetWindowPositionVars().
Fix slowdown when many mobjs on moving sector

Thanks to Platinum Shell on the Doomworld forums for bringing this
problem to my attention: When there's a large amount of monsters (and
especially blood splats) on a moving sector, there's some seriously
nasty slowdown. An example of this is MAP30 in Doom II: put god mode on,
leave a few monsters to spawn and fight amongst themselves for a few
minutes, and then lower one of the floors and you'll see what I mean.
The changes I've made in this commit greatly speed up things, with no
adverse side effects as of yet.
No upward thrust from Arch-vile's fire attack...

...if the player is using the IDCLIP cheat. This is then consistent with
all other forms of attack.
Further optimizations to handling moving sectors
Fix compile errors on SDL2 configuration
Delete unused files
Merge pull request #57 from TheLonerD/sdl2fix

Fix compile error on SDL2
Resize window correctly in widescreen mode
Press window's maximize button to go fullscreen
Toggle fullscreen in widescreen mode

Recent changes allowing widescreen mode in a window required a few
changes to the ToggleFullScreen() function.
Correct amount in message on ammo pickup

When player picks up ammo, the messages displayed are hardcoded to
indicate "one cell", "four shells", etc., but when the lowest and
highest skill levels are chosen, the player is actually given double the
amount. (Also, there's a difference between clips dropped by Zombiemen,
and clips that aren't.) This commit implements 4 new dehackable messages
to display the correct amount.
Display message when picking up half a clip

When picking up a clip dropped by a Zombieman in a skill level other
than the first and last, only half a clip is given, so display "You
picked up half a clip." Also fixed an issue with previous commit.
More accurate window resize in widescreen mode

Yesterday's implementation caused a gap at the bottom of the window that
widened with each resize of the window. This fixes that. Plus a bit of
reformatting.
Fix stretched cursor sometimes showing in center...

...of window when bringing up menu, before it moves to bottom right
corner.
Improvements to saving window position
Don't show alternate ammo pickup messages...

...if they have been DeHackEd.
Save fullscreen setting immediately when changed