#252 837/835 tweaks

[Art Eaton]

https://github.com/aethelwulffe/SunCoast_OpenEMR/tree/837/835-X12-tweaks

Adds BPR04 element. Creates exception for adjustment reason '144' (which otherwise results in negative balances when it is an "advisory" report, and not really an AR element). Added required element tweak for Florida Blue Medicaid.