Bug 7246 add offset/length and where options to rebuild_zebra

Bug 7246 add offset/length and where options to rebuild_zebra

This patch reimplement a feature that is on biblibre/master for Koha-community/master

It adds 4 parameters:
* offset = the offset of record. Say 1000 to start rebuilding at the 1000th record of your database
* length = how many records to export. Say 400 to export only 400 records
* where = add a where clause to rebuild only a given itemtype, or anything you want to filter on

Another improvement resulting from offset & length limit is the rebuild_zebra_sliced.zsh
that will be submitted in another patch.
rebuild_zebra_sliced will slice your all database in small chunks, and, if something went wrong for a given slice, will slice the slice, and repeat, until you reach a slice size of 1, showing which record is wrong in your database.

Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>
Removed mention of -l option for limiting number of items exported, as requested
by QA manager. This can be re-added in a later patch.

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>