Update master from staging - multiple changes

@natmey @critzo @sifrwahid @jheretic @georgiamoon - Please review, per my email.

1. Download (routers) page: Some text changed, mostly simplification and adding a link to installing and configuring instructions.
2. Removed old Common Configs and Added "Common Hardware Setups" and "Advanced Hardware Setups" in CCK -> Install+Config
3. Changed "Get Help" menu to "Documentation".
4. Moved Wireless Challenges to Networking from Planning
5. Added "For Organizers"" menu - goes to CCK landing page and various sections.
6. Small firewall addition to Configure Commotion under advanced

Merge and re-build production site when ready!