[DB] Schema update for reseller members
[NF] Add FANOUT type port for resellers

For resellers, we need to enforce the one port - one mac - one address rule
on the peering LAN. Depending on switch technology, this will be done using
a virtual ethernet port or a dedcaited fanout switch. A fanout port is a port
that sends a resold member's traffic to a peering port / switch.

I.e. it is an output port to the exchange to connects to a standard peering
input port.
[NF] Function to check if resller mode is enabled
[IM] Adding form element for resller fields in customer form
[NF] Function to return resllers names array
[IM] Setting resller data then adding updating customer
[DB] Link virtual interfaces for fanout and peering
[DB] Link pysical interfaces for fanout and peering
[IM] Not allowing to change reseller state if resller have resold customers
Merge branch 'nf-resellers' of https://github.com/inex/IXP-Manager into nf-resellers
[DB] Physical interfaces do not have to have a fanout port
Merge branch 'nf-resellers' of https://github.com/inex/IXP-Manager into nf-resellers
[IM] Updating entities and proxies after db schema canges
[IM] Showing reseller information in customer overview. [Solves IXP-1]
[IM] Rename overview section billing to details
[IM] Hiding billing details if 'reseller.no_billing_for_resold_customers' in application.ini is set to true and reseller mode is enabled. Solves IXP-2
[IM] Changes to Virtual Interface page for fanout. Solves IXP-3
[IM] Checking if if customer have related Physical interfaces then changing resller state, reseller and resold customer state.
[IM] Adding form Fanout port form element into physical Interface add edit form. Part of IXP-4
[IM] Updating proxies