Ping code and code map should be unique for all 1601 and 900x tags

[xhoenner]

Apart from 1105 and 1303 code maps which have ping codes that have been highly replicated, the ping code and code map combination (= transmitter_id) should be unique for each tag. There should consequently never be two identical transmitter_id values in the sensor table for any 1601 or 9001, 9002, 9004, or 9006 tags.

This lack of constraint in the UI created the data errors listed in https://github.com/aodn/aatams-content/issues/50 and subsequently duplicate detections. The logic indicated above should be implemented both on the tag creation and edit pages.

@fjaine feel free to correct me if I'm wrong!

[fjaine]

Agreed @xhoenner - that's how I understand it too.