[ER] allow renaming of network interfaces without enabling them
In Interfaces>(assign) you can create a new interface. The first one is WAN, the second is LAN, and then it starts with OPT1, OPT2, etc.
So now you want to rename OPT1 to DMZ, because that's what it will be at some point in the future, but you have no intention of using that interface right now. Just after it's assigned, it's not enabled, so when you click on that interface in the table or select it from the drop down menu Interfaces>OPT1 you only are given the choice to enable the interface, but there is no way of setting the name for the interface.
The only way to do this is to enable the interface, then rename it, and then disable the interface.
First that's not very intuitive, and second, even while an interface is disabled things like aliases or descriptions should be editable, IMO.
Now that the fields on interfaces.php aren't hidden upon disabling the interface, we don't want to handle disable separately from everything else, as that discards all the changes other than disabling the interface. Everything else with handling bringing down of interfaces is still handled correctly. semi-related to Ticket #2453