Travis CI: site documentation update at 2014-04-19 23:26:11 UTC.

Commit: https://github.com/urho3d/Urho3D/commit/76d5ffdcf88f424366c58483f9d79caae2fb5215

Message: On OS X + Intel, use dummy color textures for shadow maps to work around a driver bug. Fixes #225.