schemas/vegbien.ERD.mwb: Fixed lines

schemas/vegbien.ERD.mwb: Adjusted lines. Adjusted position of locationdetermination to put location directly next to locationevent. Expanded location to fill newly-available space.

schemas/vegbien.sql: locationevent: Renamed authorlocationcode to authoreventcode to be consistent with the table name. Note that for our current datasources, the plot = the plot event, so the authoreventcode and authorlocationcode/authorPlotCode will be the same.

mappings/VegCSV-VegBIEN.specimens.csv: Changed VegCSV term fieldNumber (from DwC) to recordNumber to be consistent with the TDWG meaning of fieldNumber, which defines it as the author code for the event, not the organism (what VegBIEN calls the authorlocationcode and VegBank calls the authorObsCode)

mappings/VegCSV-VegBIEN.specimens.csv: Comments: Removed no longer applicable comments about XPath syntax added to affect sort order

mappings/VegCSV-VegBIEN.specimens.csv: height: Removed mapping to plantobservation.overallheight, since the height is a stem field rather than a plant field. Note that a height in the organisms table will be mapped to the height in a single stemobservation for that plant, with NULL sourceaccessioncode and authorstemcode. Note also that this change is possible because no mapped datasource yet provides a valid overallheight with multiple stems or that differs from its single stem's height. (Although SALVIAS sometimes provides both a stem height and an organism height, that height is always either the same, or the organism height is invalid. See <https://projects.nceas.ucsb.edu/nceas/projects/bien/wiki/SALVIAS_issues#Some-organisms-have-one-stem-but-different-heights-in-the-organisms-and-stems-tables&gt;.)

mappings/DwC2-VegBIEN.specimens.csv: establishmentMeans: Removed obsolete mapping to growthform, since growthforms and cultivated/native information are no longer merged into one field in VegBIEN (which they were when this mapping was created)

mappings/VegCSV-VegBIEN.specimens.csv: decimalLatitude/decimalLongitude: Added _nullIf suffix for mergability with VegCSV-VegBIEN.specimens.csv

mappings/VegCSV-VegBIEN.specimens.csv: coordinateUncertaintyInMeters: Added _noCV suffix for mergability with VegCSV-VegBIEN.specimens.csv

mappings/DwC2-VegBIEN.specimens.csv: catalogNumber: Added _if wrapper for mergability with VegCSV-VegBIEN.specimens.csv