various adds

1. • added new schema for groups
     There can be up to 8 groups of devices, the names of the groups can be set in config
     Each groups counts the number of devices home (up) and away(down/expired)
     They are shown as variables
     Unifi_count_groupname_Home == number of device up
     Unifi_count_groupname_Away = number of devices not up
     Unifi_count_groupname_lastChange = datestamp of last count change
     A device can be added/ removed in each devices edit or in menu/manage groups
     The manage group option allows to add eg all wifi or lan devices to a group
     and you can eg add/remove 10 individual devices on one screen faster than editing 10 devices
     There is a a report on the groups, memebers etc in Print parameters
   • several device model texts had typos
   • various menu cosmetic changes

2. fixes

   • block / unblock wifi devices had a cosmetic error message
   • the site id name was always default, now can be set in config (not test)