bug_6253: Unified member Search()

bug_6253: Unified member Search()

Removed SearchMembers() and replaced with more generic Search()
Amended Search() to try cardnumber first
Replaced SearchMembers() calls with Search()
Replaced SELECT with Search() where appropriate
C4::SQLHelper:
- added support for '' key for search filter.
- when passing an array to filter, join with OR (rather than AND)
- added support for key => [val1, val2] in filter
- did not document - there was no input documentation to start with,
  and SQLHelper should be replaced with something better anyway

Signed-off-by: Liz Rea <lrea@nekls.org>
(again - testing merge issue)
The functionality of the patch seems to be maintained with Biblibre's changes.

I tested the following:
Extended attribute searching: works
3 part name searching: works
2 part name searching: works
1 part name searching: works

From:
mainpage.pl
members-home.pl
	Patron search limited by branch: Works
	Patron search limited by patron category: works
	Ordering by cardnumber instead of surname: works
The "Check Out" field in the masthead.

Circ Autocomplete is not reliably functional at this time, but the problem appears to predate this patch.
Signed-off-by: Ian Walls <ian.walls@bywatersolutions.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>