1) Tidies up the Datasource Dialogue now the version options are gone.
2) Tidies a comment in info.c.
3) Increments all version numbers to 07.01.0003 to take account of recent
revisions.

Regards, Dave Page

Now only wchar.c is shared by fronetnd/backend.

When no suitable YACC is configured, supply useful informational messages
to users.  (Same way flex has been handled for a while.)