LP#1702557-Make Acq MarcEditor Just Have Save Button

LP#1702557-Make Acq MarcEditor Just Have Save Button

Like the changes to the z3950 marceditor UI, and serials,
make the Acq marceditor have a simple Save button, instead
of the Modify + Save Edits buttons needed to save a change.
Same change as in 1710405, et al. Note this also fixes a
propagation issue that prevented changes from marceditor's
scope.marcXml from making it to the modal controller scope,
and being saved. Props to miker for helping me debug this!

Signed-off by: Cesar Velez <cesar.velez@equinoxinitiative.org>