Fix tests for "ended" flag in relationship edits

When a relationship has an end date, its "ended" flag must be set,
too. Fix the expected data for "add relationship" edits accordingly.

This test currently fails.
Add tests for removing dates from a relationship

The mini relationship editors currently don't allow removing a (begin
or end) date from a relationship. This adds new tests that demonstrate
the problem.
Add missing begin_date/end_date to a test
Display series/instrument ARs on relationship pages
Allow removing dates from the mini rel. editor

Unfortunately, the mini relationship editor works from form data that
has not yet been validated (and normalized in the process). In
particular, the code in MB::S::Form::Field::PartialDate that sets
year/month/day for empty dates to undef is not run, nor is the code in
MB::S::Form::Field::DatePeriod to set the "ended" flag when an end
date is present.

Since refactoring the hook for the mini relationship editor is too
heavy a change for a post-schema-change planned hotfix, this commit
provides workarounds to allow removing dates. It fixes the tests from
the previous three commits.

This also fixes MBS-7545: Empty URL edits were created from the
release editor that differed in the normalized/non-normalized
representation of empty dates.
MBS-7539: Changing the ordering type is always an autoedit
MBS-7559: Sort name guess case is missing from series alias pages
MBS-7556: Fix URL cleanup on edit URL pages

The URLCleanup function used to take a Knockout observable
"errorObservable" as a parameter and had a default to always treat it
as the empty string when the parameter was null. This has changed to
an errorCallback function parameter, but there was no default for it.
Therefore, the edit URL page that didn't provide a callback caused a
type error, and the cleanup code wasn't run.

This commit reinstates the previous behaviour: If no callback is given
when URLCleanup is called, it defaults to a function that always
returns the empty string.
Merge remote-tracking branch 'chirlu/mbs-7556' into hotfix1-2014-05

* chirlu/mbs-7556:
  MBS-7556: Fix URL cleanup on edit URL pages
MBS-7559: Sort name guess case is missing from series alias pages
Merge branch 'mbs-7559' into hotfix1-2014-05

* mbs-7559:
  MBS-7559: Sort name guess case is missing from series alias pages
MBS-7539: Changing the ordering type is always an autoedit
Merge branch 'mbs-7539' into hotfix1-2014-05

* mbs-7539:
  MBS-7539: Changing the ordering type is always an autoedit
Merge remote-tracking branch 'chirlu/hf3' into hotfix1-2014-05

* chirlu/hf3:
  Display series/instrument ARs on relationship pages
Merge remote-tracking branch 'chirlu/hf2' into hotfix1-2014-05

* chirlu/hf2:
  Allow removing dates from the mini rel. editor
  Add missing begin_date/end_date to a test
  Add tests for removing dates from a relationship
  Fix tests for "ended" flag in relationship edits
Merge branch 'hotfix1-2014-05' into beta
Merge remote-tracking branch 'bitmap/mbs-7539' into beta
Merge remote-tracking branch 'bitmap/mbs-7559' into beta