* removed unneeded includes
* moved global brightmap to GPalette
* took Build tile init code out of the FTextureManager class, because this code is not compatible with how real Build games need to go about it, making the texture manager not shareable.
* removed dependency on higher level info from the Image class.
* moved the sprite renaming out of the file system entirely into a caller-provided callback.
* renamed several functions to closer match the terms of a file system.
* moved the VM interface out of the implementation.
- replace swapvalues with std::swap globally.
- added some additions to utility code from Raze, mainly to reduce file content differences.
- reduced some unused utilities
Mainly done to isolate the calls that actually manipulate the global frame buffer.
V_Init alsoi initialized some palette data, which was moved to V_InitPalette and did something entirely different when running a restart as opposed to an initial start.