Moves system level setting of the hostname to the "apply" stage of luci value settings

Per Issue #180 this pull request modifies the way hostnames are added to the system by pushing all system-level manipulation of the hostname into a init.d script. 

To Test: 
1) Flash a node with this branch included
2) Connect to node and click "setup wizard"
3) Change the host-name to one of your choosing on the first page
4) On the next page the hostname field in the header should still read "commotion"
5) On the "Save and Apply" page click the "Start Over" button
6) If the hostname changes should now be reverted 
7) Add a new hostname
8) On the "Save and Apply" page click the "Save and Apply" button
9) Log into the administration menu
10) In the header should state the new hostname you added as your hostname.