Cross-field validation for TOMSwift

[jchate6]

Valuable to make this as comprehensive as possible to minimize user errors but hard to explain all possible combinations. Best approach is probably for dev to sit down with astro and work through them. Two examples named during the meeting were that if GRB type is filled in then trigger type must be specified, and that time and date formatting should be verified.
from:

• Feedback on tom-swift module from Swift Operations Team tom_base#703