Added more System Options
Added more System Options

Added links to new sections; Installing Apps & Updating emoncms.
Also made clear that this guide applies to Wheezy and not Jessie.
jesjimher/emoncms,inverse/emoncms,chaveiro/emoncms,inverse/emoncms,thaipowertech/emoncms,thaipowertech/emoncms,emoncms/emoncms,jesjimher/emoncms,chaveiro/emoncms,chaveiro/emoncms,jesjimher/emoncms,jeremypoulter/emoncms,emoncms/emoncms,inverse/emoncms,emoncms/emoncms,jesjimher/emoncms,emoncms/emoncms,jeremypoulter/emoncms,chaveiro/emoncms,thaipowertech/emoncms,inverse/emoncms,emoncms/emoncms,thaipowertech/emoncms,jeremypoulter/emoncms,jeremypoulter/emoncms