Use eval in eg_staged_bib_overlay.

Use eval in eg_staged_bib_overlay.

Wrap the parsing of MARC from input files in eval blocks with an error
handler to skip to the next record.  I have encounterd bad records
that have stopped the processing of the rest of the file.  This
occurred the very first time I used this script.

Signed-off-by: Jason Stephenson <jason@sigio.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>