Added GYP build files. GYP files are needed for integration with chromium and cross-platform build for glsl translator. It would really be nice if we did not have to maintain two build systems. For now I have only moved the GLSL translator to gyp build system. Please note that the gyp files awkwardly have build_ prefix so they do not conflict with the manually-maintained sln files.
Review URL: http://codereview.appspot.com/885043

git-svn-id: https://angleproject.googlecode.com/svn/trunk@98 736b8ea6-26fd-11df-bfd4-992fa37f6226