Fix the error message (copied from users) on queue disable
Prohibit creating tickets in disabled queues

We check if ->Disabled != 1 because ___Approvals are Disabled == 2, but
must allow tickets to be created in them.  See 2e6dd76 and 0d17c8d.
Preserve the current simple search query for easier refinement

More times than I can count I've typed in "trs keyword" and then wanted
to quickly refine the search by another keyword.

This also kills the JS onfocus logic in favor of the much simpler HTML5
placeholder attribute.
Allow the browser to remember past simple searches
When cloning, don't skip duplicate scripaction/conditions on import
Serializer/Importer: Simplify clone logic by skipping class methods

Short-circuit the class-specific logic in Serialize and PreInflate if
cloning is in progress.  These custom class-level methods all deal with
doing ID => UID translation, or ensuring that duplicate records are not
created, neither of which are necessary when cloning.
Warn, and deprecate for 4.4, the old UpdateCustomFields call convention

This API was marked for deprecation in RT 3.6 -- finally start warning
about it so that it can be removed.
Remove deprecations on ->Limit* helpers on CustomFields

Despite assuming that all CFs apply to tickets, these are useful helper
methods.  Document their restrictions, but leave them in-place.
Remove support for $LinkTransactionsRun1Scrip

The option was initially added to provide backwards compatible behaviour
for 3.4.  We've been recording two link transactions since 3.4.5 and
running scrips on both by default since 3.8.0.  Anyone relying on this
option can adjust their scrips to ignore one of the transactions.

The test file required more adjusting than I would have preferred since
it was written around the assumption of toggling this option.  In the
process of making it pass, I removed the confusing cumulative behaviour
of link_count() by having it reset whenever called.  I also fixed a
minor test bug which called AddLink when it meant to call DeleteLink
(line 170 in the new file).
Move creation of link transactions from RT::Ticket into RT::Record

Now articles and other objects will record transactions for links.