[evlatests] TIP scans and EVLA antennas

[Bryan Butler]

i just ran a TIP test.  two things of note:

1 - the EVLA antennas don't TIP.  hmph.  i'll figure out what's going
     on with further tests.

2 - despite the fact that they don't TIP, it doesn't screw anything else
     up - i.e., they go on to the next source quite happily.

so, we can tell users that they can have TIP scans in with OBSERVE files, just 
that the EVLA antennas won't TIP (for now).

	-bryan