validation/aggregating/*/*.sql, schemas/vegbien.sql, lib/runscripts/validations.pg.sql.run, inputs/bien2_traits/validations.sql: added _ to beginning of each view name so the validation views would sort at the top in the datasource's tables list. this will also make the validation result sets easily distinguishable from the data tables.

validation/aggregating/*/*.sql: renamed views to match the current naming scheme in the DB. these files still need to be kept up-to-date because there are some queries that haven't been implemented yet, and therefore exist only in these files, not the DB.

schemas/util.sql: ifnull(): use COALESCE instead, because it turns out that MySQL's IFNULL is just a special case of this

added inputs/bien2_traits/validations.sql, from validation/aggregating/traits/BIEN2_traits/bien3_validations_traits_original_mysql.VegCore.sql

inputs/input.Makefile: $(svnFilesGlob): added validations.sql

bugfix: validation/aggregating/traits/BIEN2_traits/bien3_validations_traits_original_mysql.VegCore.sql: added util to search_path so that IFNULL would link to util.ifnull()

schemas/util.sql: added ifnull(), equivalent to MySQL's IFNULL (Postgres auto-lowercases the name)

lib/sh/util.sh: stderr_matches(): documented that the purpose of not redirecting fd 2 back to fd 2 is to allow log-filtering out an otherwise-confusing benign error

lib/sh/util.sh: ignore_err_msg(): documented that unlike `|| true`, this suppresses only errors caused by a particular error message, rather than all error exit statuses

bugfix: lib/runscripts/validations.pg.sql.run: updated table match pattern to include the type prefix that validations queries now contain