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

bugfix: lib/sh/util.sh: $sed_cmd: make output unbuffered, so that running e.g. bin/my2pg at the command line produces output as each line is read

bin/my2pg: replace MySQL ` quotes with " quotes to support exports that were generated without ANSI_QUOTES mode. (this replacement only applies to schema exports, not data.) ANSI_QUOTES is only available with mysqldump --compatible modes that also include NO_TABLE_OPTIONS, which omits important table options such as comments. in particular, these comments are part of schemas/VegCore/VegCore.ERD.mwb but were not being included in VegCore.my.sql.

schemas/VegCore/VegCore.ERD.mwb: taxon_string: removed parsed_taxon_assertion field, since there may be more than one parsing (TNRS result) for a given taxon_string. the parsing relationship can better be represented by adding a parsed_taxon_assertion whose taxon_assertion.string points to the parsed taxon_string. getting the parsed_taxon_assertion for a taxon_string now requires joining on parsed_taxon_assertion using a backwards instead of forwards fkey, and filtering the corresponding assertions to include only the ones for TNRS (of the desired TNRS version). documented that taxon_assertion.string was previously the concatenated matched name, but is now the TNRS input name. the concatenated matched name is still in parsed_taxon_assertion.matched_taxon_concept->:taxon_name.unique_name.