updated the static pages a bit

- point to the FAQ(!) instead of just answering some faqs (if I get 1 buck whenever someone asks them in the forums or IRC...)
- Update Mono/Visual Studio version (removed the VS version because both 2010 and 2012 and maybe even still 2008 should work at the moment), Add MonoDevelop as it is Open Source (Maybe we should recommend SharpDevelop, Xamarin Studio, too? Does anyone use them?)
- Credit the platform icons only where they are actually used
- Link the nice auto-generated GitHub contributor graphs
- remove COMMENTS placeholder