lib/sh/util.sh: rethrow: documented why can't use `(exit "$e")` (bash bug that prevents errexit)

bugfix: /README.TXT: Maintenance: VegCore data dictionary: apply new data dict mappings: need to use import rather than mappings runscript target, to rename the staging tables

bugfix: /README.TXT: Maintenance: VegCore data dictionary: also need to apply new data dict mappings on vegbiendev

fix: /README.TXT: Maintenance: VegCore data dictionary: added steps to apply the new data dictionary mappings to the datasource mappings and staging tables

bugfix: lib/runscripts/util.run: $auto_ignore: need to unexport it so don't pass this to invoked scripts except through fwd()

added inputs/run, which runs all the inputs' runscripts using the new auto-forwarding

bugfix: lib/runscripts/util.run: auto_fwd's fallback() must be set after auto_ignore's fallback() to overwrite it (auto_ignore should only apply if an error would otherwise have been generated by the fallback)

lib/runscripts/util.run: fwd(): support subdirs that don't contain a runscript, so that the default value of @subdirs will work in most cases

lib/runscripts/util.run: fwd(): set default @subdirs (`{.,}*/`)

lib/sh/util.sh: added enter_top_dir and use it in in_top_dir