This is a lot of changes in a lot of code because nothing here was abstracted into the sound system. :(
Hopefully most of the affected code here can be tossed out soon, it's not pretty.
This is going to be a lot of work consolidating the 3 frontends' settings but a necessary evil for eventually getting Shadow Warrior to work as it is quite lacking here.
- consolidated Polymost precaching and removed precaching for static tiles because they now are always loaded.
- removed cache configurability. On modern systems this is relatively pointless - allocating 50 or 100 MB is a non-issue - and the cache is due for replacement anyway.
The EDuke32 and RedNukem frontends are working, Blood isn't yet.
Notes:
many of the CMake variables and its output still refer to zdoom. Before changing that I wanted to make sure to be able to commit something that works.
support code for Windows XP has been entirely removed. On Windows this will only target Vista and up.
the crc32.h header had to be renamed to deconflict from zlib.
several Windows API calls were changed to call the A-versions directly. Weirdly enough there were places that defined their parameters as T types but in a non-working way.
removed some remaining editor files and support for the native software rendering only Windows backend.
in a few simple cases, replaced 'char' with 'uint8_t'. The code as-is depends on chars being unsigned which is non-portable. This needs to be carefully reviewed.
