game entry file names changed to canonical version

games/0_ad.md

@@ -0,0 +1,24 @@
+# 0 A.D.
+
+_0 A.D. is a free, open-source, cross-platform real-time strategy game._
+
+- Home: https://play0ad.com/, https://sourceforge.net/projects/zero-ad/
+- Media: <https://en.wikipedia.org/wiki/0_A.D._(video_game)>
+- State: beta
+- Download: https://play0ad.com/download/
+- Keywords: strategy, real time
+- Code repository: https://github.com/0ad/0ad.git (mirror), https://svn.wildfiregames.com/public/ps/trunk/ (svn)
+- Code language: C, C++
+- Code license: GPL-2.0
+- Code dependencies: libogg, libvorbis, libxml2, OpenAL, SDL2, zlib
+- Assets license: CC-BY-SA-3.0
+
+## Building
+
+- Build system: Custom
+- Build instructions: https://trac.wildfiregames.com/wiki/BuildInstructions
+
+See [instructions](https://trac.wildfiregames.com/wiki/GettingStartedProgrammers)
+
+Has solution files for MSVC 2015, might also use premake.
+