csvs.py: TsvReader: Also interpret '\t' as a tab, to provide a mechanism for encoding embedded tabs

tnrs.py: gwt_encode(): Escape special characters in the string instead of removing them, so that TNRS receives the original name rather than a modified version. This will help make the submitted names match up with the returned Name_submitted.

strings.py: Added json_encode()

strings.py: Added esc_quotes()

schemas/vegbien.sql: placepath.canon_placepath_id: Changed hierarchy comment to match the taxonpath.canon_taxonpath_id comment, but with a two-level hierarchy of datasource name -> accepted name. This may later be changed to a three-level hierarchy like taxonpath.canon_taxonpath_id depending on how GNRS works.

schemas/vegbien.sql: taxonpath.canon_taxonpath_id: Changed comment to specify that taxonpaths should now be linked in a three-level hierarchy of datasource name -> concatenated name -> accepted name

schemas/vegbien.sql: taxonpath, placepath: Changed "scrubbed" to "accepted" to emphasize that the name is the accepted name returned by TNRS or GNRS, rather than merely the matched name

mappings/VegCore-VegBIEN.csv: non-TNRS taxonpaths: Store the concatenated identifyingtaxonomicname in a separate taxonpath owned by the TNRS datasource, so that it will match up with (and create a link to) the corresponding submitted TNRS name's taxonpath. This in turn is linked to the TNRS-determined accepted name, thus creating a three-level hierarchy of datasource name -> concatenated name -> accepted name.

mappings/VegCore-VegBIEN.csv: taxonomic terms: Remapped the concatenated taxonomic name to new identifyingtaxonomicname to use it directly to match up with the TNRS submitted name. Continue to map scientificNameWithAuthorship to taxonomicnamewithauthor.

schemas/vegbien.sql: taxonpath: Renamed plantcode to identifyingtaxonomicname so that it can be used to store the concatenated taxonomicname that gets scrubbed. This enables ignoring the name components when the full name is specified, so that when a TNRS submitted name's matched components are included in its taxonpath, this will not prevent a datasource's concatenated name (without the matched components) from matching up with the corresponding TNRS submitted name.