Use copy owning library as the context for finding best hold sort order setting

[Mike Rylander]

In the olden days before best hold sort order and proximity adjustment, there was no need to consider any context org other than "here", because the choices were, essentially, FIFO or Traditional applied within the hard-boundary range. However, now we need to decided whose rule to follow, and the most correct arbiter of that is the owning library of the call number of the copy. We avoid copy circ lib because that can change with floating copies.

Code at: http://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/miker/change-best-hold-context-org

This applies cleanly to 2.4+.

[Ben Shum (bshum)]

Been testing this on one of our systems, so far so good.

Picked to master, rel_2_5, and rel_2_4. Thanks Mike!