mappings/: Split Veg+.terms.csv into VegCore.csv and Veg+.unmapped_terms.csv

mappings/Veg+.terms.csv: Removed terms that are in mappings/Veg+-VegCore.csv

mappings/Veg+-VegCore.csv: Added sources where missing

mappings/Veg+-VegCore.csv: Added Source and Comments columns from mappings/Veg+.terms.csv. Reordered columns to put Comments first.

mappings/Veg+.terms.csv: Removed duplicate entries for stem_id/stemID, collector

inputs/import.stats.xls: Updated import times

inputs/REMIB/Specimen/: Filter out invalid, frameshifted rows so they don't produce errors in the import or anomalies like thousands of taxondeterminations for one taxonoccurrence. This involves moving the CSVs to Specimen.src and using a create.sql to create the filtered table.

mappings/VegCore-VegBIEN.csv: Forward occurrenceID to taxonoccurrence.sourceaccessioncode when there is no other taxonoccurrence.sourceaccessioncode, to ensure that taxonoccurrence is uniquely identified so that there is one taxonoccurrence per organism

mappings/VegCore-VegBIEN.csv: taxonoccurrence.authortaxoncode alternatives: Use _first instead of _alt because when one of these fields is present, it can be used directly even if it's sometimes NULL, without needing to spend a lot of time _alting together fields that won't be used. Datasources where the authortaxoncode is sometimes NULL usually have a separate sourceaccessioncode for the taxonoccurrence. (In the rare case that they don't, they should map a non-NULL field to recordNumber or tag to ensure that taxonoccurrences can be uniquely identified.)

mappings/VegCore-VegBIEN.csv: Mapped tag to taxonoccurrence.authortaxoncode when the record is an organism, in case there is no other ID for the taxonoccurrence. This fixes a bug in FIA and TEAM data where all organisms in a plot used the same taxonoccurrence because taxonoccurrence was not properly constrained, causing the loss of individual taxondeterminations on each organism.