1)bugfix in webmgr.js

2) add new demo mode:
- get a picture from the camera
- extract the main colors

TODO:
- add a button for colorpicker
- display colorpicker in full screen mode
- add frame to display the selected color (input box ? )
- connect the selected color to the variable used for NFC communication
new plugin for colorpicker: spectrum.css/js
new demo mode :
 * take a picture
 * extract the main colors
 * select one of these colors to be sent by NFC

bugfix
Merge branch 'master' of https://github.com/jjacques22/buddiesjewel