schemas/VegCore/VegCore.ERD.mwb: individual: added tag_history hstore to store custom identity attributes

schemas/VegCore/VegCore.ERD.mwb: taxon_string: documented that to get the parsed_taxon_assertion (TNRS result) for a taxon_string, you would join using the SQL dotpath taxon_string.string<-taxon_assertion(string)::parsed_taxon_assertion[source='TNRS.version'] (see wiki.vegpath.org/SQL_dotpaths). important how-to comments such as this one are now included in the version-controlled MySQL schema file itself, not just the .mwb file and the staging copy on vegbiendev.

bin/my2pg: use s!...!...! when either the regexp or the replacement contains / , to avoid unnecessary \-s

bin/my2pg: commenting out table options: added explanatory comment, because it is not obvious from the regexp what this does

lib/sh/db.sh: mysqldump(): don't use --compatible=postgresql when the table structure is being exported, because this removes the table options (which include the COMMENT attribute). --compatible=postgresql remains on in data-only mode because embedded ` in data cannot easily be distinguished from ` around column names, so ANSI_QUOTES is needed to do the translation to " (and data sections do not contain table options). note that all --compatible modes that offer ANSI_QUOTES unfortunately exclude the table options, and there is no way to run a SQL query to set the SQL mode before beginning the dump, so ANSI_QUOTES translation must be handled by my2pg instead.

bin/my2pg: comment out table options (http://dev.mysql.com/doc/refman/5.5/en/server-sql-mode.html#sqlmode_no_table_options) instead of removing them, because they include table COMMENTs, which contain important metadata such as table definitions. (note that table COMMENTs use a slightly different syntax than column COMMENTs, so the table COMMENTs will not be commented out twice.)

bin/my2pg: comment out COMMENTs instead of removing them so that they will be included in the PostgreSQL translation. COMMENTs contain important metadata about columns, such as definitions and the meanings of integer flag values.

inputs/{.,}*/*.schema.sql: regenerated using the instructions in bin/my2pg. this primarily replaces timestamp with text/*timestamp*/ (to preserve indefinite dates).

bin/my2pg: added instructions for regenerating *.schema.sql whenever this script is changed

bin/my2pg: COMMENT: also match COMMENTs with embedded ', because there will only be one COMMENT per line, so the contents of the COMMENT can just extend to the last ' on the line