Moves Deferred-related code into a separate module. Context handling has been simplified in _Deferred.resolve and jQuery.when has been refactored for clarity (and minor optimization).

Revert "Fixes #8353. Adds a catch block in resolveWith so that the finally block gets executed in IE7 and IE6."

This reverts commit cacea6f7.

Make a new jQuery.support.noCloneChecked - splitting apart the previous feature detect relating to clone in IE, fixes the last remaining issue with IE 9 RC. Fixes #8365.

Fixes #8353. Adds a catch block in resolveWith so that the finally block gets executed in IE7 and IE6.

Makes the promise method of Deferreds a bit more readable by not using the variable declared as parameter trick anymore.

Revert "Adds an invert method to promises that returns a "inverted" promise that is resolved when the underlying deferred is rejected and rejected when the underlying deferred is resolved."

This reverts commit 4e975430.

A temporary workaround for #8018 that avoids any chance of compatibility-breaking changes until a proper fix can be landed in 1.6.

- Use fresh div instead of one outside the test-fixture
- make sure the empty string test tests actually that (not 0% 0%)
- actually test for < -10000 (#7193)
- fixed some whitespace issues

Fixes #7912. Make sure .cur() only returns 0 as fallback value when it needs to ("", auto, undefined, null).

This change makes .cur() more .cssHooks friendly. .cur() now returns the unmodified value by
.css() if it isn't a number, number-alike or a value that needs a fallback to 0.
This way fx.start doesn't need to be recalculated for complex values.

Only perpetrate the .toJSON hack on data caches when they are attached to a plain Javascript object. Part of the continuing saga of #8108.

Fixes #8297. Makes sure response headers with empty values are handled properly and do not prevent proper parsing of the entire response headers string. Unit test amended.

This reverts commit bb940851, reversing
changes made to 3ad8dd24.

Conflicts:

	src/effects.js

Fixes #7922. Copy the donor event when simulating a bubbling submit in IE so that we don't accidentally stop propagation on it. Remove a bunch of return statements that could also cancel the event. DRY out the liveFired change from #6359 by moving it to the trigger() function.

Fixes #8277. Sets data to undefined rather than null when it is not provided in ajax helpers so that it won't revent data set in ajaxSettings from being used. Unit test added.

Update jQuery.data to use jQuery.noop for toJSON hack instead of an additional superfluous function.

Fix stupid error.

Adds tests for the fix to #6781.

Follow up to ba43d373 which apparently
didn't fix the problem completly on Mac OS X.

Follow up to 462bb1f6.