eRx Refactoring markTx.php

Revisiting this code after four. I am looking at some of the original thoughts that went into it and it has all changed. The only thing this fragment needs to do is update the table to transmit.

I am questioning if this file is needed at all. The system does need to mark what was transmitted and on what date was it transmitted. But does there need to be an ajax call to do all that?

Looking for some thoughts on how to accomplish this differently and maybe do away with this file.

@Carter @visolveemr