Revert "Add checkedValue binding that works with the checked binding to allow for arbitrary values for checkboxes and radio buttons."

This reverts commit 4db92498ff293d57b2626254b9c33d580f098bea.
Merge pull request #973 from knockout/954-remove-2.3.0-checkedValue

Revert "Add checkedValue binding"
Increase timeouts in tests so that they pass in Firefox.
Merge pull request #967 from knockout/967-fix-tests-failing-in-ff

/spec/runner.html failure
If the optionsCaption value is null or undefined, don't show the caption.
add a test for undefined that also needs to unwrap the observable
Merge pull request #997 from knockout/997-deactivate-caption

Computed optionsCaption not disappearing fully in latest build
Update version to 2.3.0rc
Revert "Revert "Add checkedValue binding that works with the checked binding to allow for arbitrary values for checkboxes and radio buttons.""

This reverts commit fac900a973bcac3fa58d2d24299d9c31987e5a39.
Merge branch 'version-3.0.0-development' into merge-2.3.0-updates

Conflicts:
	src/binding/defaultBindings/options.js
Merge pull request #1025 from knockout/merge-2.3.0-updates

Merge 2.3.0 updates