Documents `{{link-to "route" someId}}` behavior
Update link_to.js

add description for `disabled` and `disabledWhen` properties for `link-to` handlebar helper.
Removes long-deprecated getPath/setPath
Set source object as context for callbacks in computed array property
Merge pull request #3366 from ssured/patch-1

Set source object as context for callbacks in computed array property
Merge pull request #3343 from trek/document-link-to-with-only-id

Documents `{{link-to "route" someId}}` behavior
Query params implementation
Use real words and use existing US English standard.
Merge pull request #3369 from eventualbuddha/infavour-to-in-favor

Use real words and use existing US English standard.
Merge pull request #3182 from alexspeller/query-params-squashed

Initial QueryParams implementation
Fixed a typo in link-to documentation
Merge pull request #3375 from graup/typo

Fixed a typo in link-to documentation
corrected mistake in Em.computed.equal docs
Merge pull request #3378 from GavinJoyce/master

Corrected mistake in Em.computed.equal docs
Replace crossLink with a markdown link
Merge pull request #3379 from bmac/fix-cross-link

Replace crossLink with a markdown link.
Merge pull request #3344 from c0urg3tt3/patch-4

Update link_to.js
Merge pull request #3350 from trek/remove-getPath-setPath-deprecations

Removes long-deprecated getPath/setPath
[BUGFIX beta] ReduceComputedProperty ignore invalidated property observers.

It can happen that several reduce computed properties depend on the same items,
because the same items are shared between computed arrays.  This will often be
the case with filter/sort chains, for instance.  When they depend on the same
item properties it can happen that an item property change is registered for a
downstream array, but a different item property observer invalidates the change.

For example, changing the priority on an item may cause it to be resorted.  This
resorting will result in it being removed and reinserted into a downstream
filtering.  However, the original priority change also triggered an observer to
update the filtering: an observer that has been invalidated by the changes
resulting from its being resorted.

- Properly invalidate such observers.
- Also update indexes even more lazily, during `flushChanges`.

Fix #3273.
Fix silly !!!! boolean conversion.