Add newer COUNTER (R4) reports

[techsvcslib]

There are several newer COUNTER (R4) reports that could be loaded into Usage Statistics. My suggestion is to start with the following:

JR2
DB2
PR1
BR3
BR5
MR1

I've already begun work on these and posted a couple of times about this to the CORAL-ADMIN steering committee, before realizing that I had not even posted an Issue statement here. I will also share a spec for comment. NOTE: The addition of these reports will also have an impact on the Usage Reports sub-module, but that module needs to be reworked anyway and I am deliberately choosing to label that work out of scope for this project.