schemas/VegCore/VegCore.ERD.mwb.run: added export_mysql (), which runs VegCore.my.sql/make ()

bugfix: lib/local.sh: $PATH: use $bin_dir_abs so the path will remain valid if the current directory is changed

lib/local.sh: added \$bin_dir_abs

bugfix: lib/util.sh: extern (): added `|| exit` after "$@" in addition to after the (), because this additional `|| exit` is apparently needed in order to propagate the exit status of the command to the exit status of the () and cause an error to abort the script properly

lib/util.sh: echo_vars (): output vars with log_level 3 so they can be excluded separately from function calls to reduce clutter in the logging output. increase the default util.run verbosity so that vars are still printed by default.

bugfix: lib/util.sh: echo_vars (): output each var separately so that each is prefixed by $PS4

lib/util.sh: inc/dec_log_level: indent commands at higher log levels using $log_indent

lib/util.sh: inc/dec_log_level: indent commands at higher log levels using $log_indent

bugfix: lib/util.sh: make (): use stdout2stderr=1 so that commands make runs are properly output to stderr

bugfix: lib/util.sh: include_guard_var (): use extern () when invoking sed so that this internal use of it isn't verbosely logged along with other external commands. note the "" around extern to refer to the function, not the alias.