Update for Phonegap

*All the issues I got stuck with is caused by the cookieStore.
*It seems that after wrapped with PhoneGap, the cookieStore data were not
be able to persist after page transition.
*So I give cookieStore completely, and move all local data storage to
localStorageService.
*Remove the "/" at the head of the subheader.html path.
Add media query

*Use matchmedia-ng to implement different preview layout on different
device width. It still does not work properly.
*Move lib js files to a separate folder.
matchmedia-ng works
Add scan barcode function

*Use ngCordova Plugin
*Can directly scan barcode without taking a picture.
Update the app icon

*Create a config folder for icon.png files
*Add a JS file in the hooks to replace the icon
Delete some redundant comments, and update the socket app.js
Slight update