LP1888723 Item location select honors context org

LP1888723 Item location select honors context org

The Angular <eg-item-location-select /> component now limits the
locations to display to those within the specified context org unit.

Instead of acting as the source of context org units, the permFilter org
units now act as limiters.  This is done so that users with global
permissions won't by default result in retrieving all copy locations.
In cases where all are needed, however, they can still be retrieved by
setting the context org unit appropriately.

Signed-off-by: Bill Erickson <berickxx@gmail.com>