Revive the cdogs-sdl project. Readers should be able to easily get information about what cdogs-sdl is, via the README and wiki pages. Users should be able to download builds for their platform. Developers should be able to check out and build using one command, without editing/configuring anything.

• Updated README
• Wiki pages, with screenshots
• Download compressed archives of builds, for Windows and Linux (OSX optional)
• One-step builds for Windows and Linux, with CMake to configure
• Platform/editor support: Windows (MSVC, MinGW), Linux (OSX Xcode optional)