schemas/util.sql: added array_fill(anyelement, integer), which doesn't require lengths for multiple dimensions

schemas/util.sql: added array_length(anyarray, dimension integer) wrapper, which returns 0 instead of NULL for empty arrays

schemas/util.sql: added array_length(anyarray), which does not require a second dimension argument

lib/sql_io.py: put_table(): documented that PostgreSQL 9.1+ now provides a way to implement insert/on duplicate select just once for each table (instead of dynamically for each insert) using the new INSTEAD OF triggers (http://www.postgresql.org/docs/9.1/static/plpgsql-trigger.html). INSTEAD OF triggers were not used when put_table() was developed, because it was necessary to support PostgreSQL 9.0, which was installed on the Mac and not easily upgradeable. it was eventually upgraded to add PostGIS, which required a complete reinstall of the DB from the staging tables, with the associated staging table reload bugs, as well as complete removal of the old Postgres version.

inputs/Madidi/: switched to new-style import

schemas/VegCore/VegCore.ERD.mwb: regenerated exports

schemas/VegCore/VegCore.ERD.mwb: categories: fixed position of place to match where it now is in the diagram. lined up boxes so that there is a visible line between the place- and occurrence-related categories.

inputs/Madidi/IndividualObservation/map.csv: translated 1:many mappings ( FieldFamilyFullName->{family,originalFamily} ) to derived columns (in postprocess.sql) to work with new-style import, which must have a 1:1 relationship between input and output columns

schemas/util.sql: added reset_col_names(), the counterpart to set_col_names(). note that this alters the map table, so it will need to be repopulated after running this function.

schemas/util.sql: mk_derived_col(): support using this function to overwrite an existing column (i.e. as a general-purpose function to perform in-place update with ALTER COLUMN TYPE USING)