OK, this time it seems to work. The last blocking problem was... a space in

OK, this time it seems to work. The last blocking problem was... a space in
recordId: (bib1,Identifier-standard) just after the comma. Adam agreed it was a bug, and it should be solved soon. But now we are aware, we can avoid putting the space !

In this commit you have all what is needed to setup a working zebra DB in Unimarc :
* collection.abs is UNIMARC specific and must be rewritten for MARC21, in marc21 directory
* pdf.properties is to be copied unmodified in the marc21 directory (can also be put somewhere else)
* rebuild_zebra.pl is SLOW, but 1 step reindexing tool, using ZOOM
* rebuild_zebra_idx is FAST, but 2 step reindexing tool, and does not use zebra. run it, it will create all biblios XML files in /zebra/biblios directory, then zebraidx update biblios in your zebra directory
* zebra.cfg is the zebra config file ;-)
* test_cql2rpn.pl is a script that will query the database and show the results. Works for me, just change the query at the beginning to get answers you expect.

What has to be done :
* benchmarking : it seems the zebraidx update is faster than lightning (400biblios/sec : 10 000biblios in 25seconds), while ZOOM indexing is slow (something like 25biblios/second) More benchmarking could be done.
* completing collection.abs for UNIMARC. I'll take care of it.
* modifying Biblio.pm to use ZOOM instead of the "zebraidx through exec" running actually. I'll take care of it also.
* modify the search API & tools & screens. I'll let the ball to someone else (chris ?) for this. I agree SearchMarc.pm can be dropped and replaced by something else (maybe a new-and-clean Search.pm package)