Improved UX for DeviceForm

1) IP textbox is automatically selected as most often used
2) it automatically sets a dummy password for simulator (as simulator
doesn't require password, but there are checks for this all across the plugin)
Avoided infinite try to close FileService

If the service-side just closed the connection, we could end up with an
infinite loop, trying to post a message on dispose, ending with exception
and another try of dispose...
Improved UX by better handling Enter and BackSpace
Providing binary warns about invalid path

It was too easy to specify empty or non-existing binary path for process IDE is about to attach.
Fixed Cascades auto start with debugger attached

Applied some 'guessing' of where the local binary is created, as it's not
as simple to be sure about as for 'regular' projects.