#392 Post-Python 3: Attempts to merge more than 17 publishers merge the first 17 records

[Ahasuerus]

Attempts to merge more than 17 publishers merge the first 17 records. The reason is that edit/pv_merge.py defines RecordNumber and Records as [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]. The logic should be changed to use the actual number of submitted publisher records instead of an arbitrary array length.