Stock 2.4.6 Portal code

Wanted to commit a baseline for all the changes made.
This commit should be the clean 2.4.6 portal code that is relevant for
now.
Applied changes for voucher creation

These changes include code supplied by unifi forums in this thread:

http://community.ubnt.com/t5/UniFi-Wireless/Custom-UniFi-Voucher-Portal/td-p/251674
plus some html formatting things and some scenic images whatnot.