TPAC Org Unit Hiding
====================

Adds support for the opac.org_unit_hiding.depth org unit setting to
TPAC, which makes out-of-scope org units disappear (except when
explicitly requested).

Org unit hiding is based on the physical_loc (Physical Location) param /
cookie, which is the closest analog to 'ol' (original location), from
which it was based in the JSPAC.

UI Changes
----------

 * All search org unit selectors
 * Holds pickup lib selector
 * Copy summary in search results page
 * Copy list in search results page
 * Copy summary in record detail page (which controls the copy grid).
 * Hold summary in record detail page