Write searching script

As with the purging script (commit eae64c15), this is a very simple
shell script that should be placed in the messages directory and
run.
Improve searching script

Ahem, this is a *lot* simpler...
Fix space to ASCII; ignore compiled files

All this time, had I paid attention, the non-ASCII error wasn't about
the messages themselves, but my actual source code.
Fix reading non-ASCII message files

Fix reading non-ASCII, non-UTF-8, ISO-8859-1 characters in local
messages.  So some errors *were* about the messages themselves.