Release checklist

Update WhatsNew.txt
Bump version number to 2.0.EVEN for stable release
- configure.ac, CMakeLists.txt: SDL_*_VERSION
- Xcode/SDL/Info-Framework.plist: CFBundleShortVersionString, CFBundleVersion
- Makefile.os2: VERSION
- build-scripts/winrtbuild.ps1: $SDLVersion
- include/SDL_version.h: SDL_*_VERSION, SDL_PATCHLEVEL
- src/main/windows/version.rc: FILEVERSION, PRODUCTVERSION, FileVersion, ProductVersion
Bump ABI version information
- configure.ac: CMakeLists.txt: SDL_INTERFACE_AGE, SDL_BINARY_AGE
  - SDL_INTERFACE_AGE += 1
  - SDL_BINARY_AGE += 1
  - if any functions have been added, set SDL_INTERFACE_AGE to 0
  - if backwards compatibility has been broken, set both SDL_BINARY_AGE and SDL_INTERFACE_AGE to 0
- Xcode/SDL/SDL.xcodeproj/project.pbxproj: DYLIB_CURRENT_VERSION, DYLIB_COMPATIBILITY_VERSION
  - increment second number in DYLIB_CURRENT_VERSION
  - if any functions have been added, increment first number in DYLIB_CURRENT_VERSION and set second number to 0
  - if backwards compatibility has been broken, increase DYLIB_COMPATIBILITY_VERSION (?)
Regenerate configure
Do the release
Bump version number to 2.0.ODD for next development version
- Same places as listed above
Bump ABI version information
- Same places as listed above
  - initially assume that there is no new ABI