Failing spec for equals of undefined/null
Fix for Object.equals for null and undefined
Fixes direct array clone

Particularly for cycles, but also takes a shortcut on ownership
verification for speed.
Leave the thunks alone

Once an object has a property change get/set thunk, even if no one is
watching, leave it alone. Chances dictate that it will be needed again,
or the object will never be needed again. Either way, removing the thunk
is a waste of time.
Rename maxLength to capacity on LruSet
Guard against accidental arguments

Some interfaces allow or disallow overriding `equals` or `index`
arguments depending on the intrinsic qualities of the collection. Per
recommendation from @daira, this commit alters those collections that
forbid these arguments such that they throw an error.

Documentation updated as well.
Add specs for find/findLast indexes
Merge pull request #54
Merge pull request #51 from kriskowal/leave-the-thunk

Leave the thunks alone
Merge pull request #47 from kriskowal/object-equals-undefined

Object equals undefined
Merge pull request #52 from kriskowal/rename-max-length-to-capacity

Rename maxLength to capacity on LruSet
Merge pull request #50 from kriskowal/shim-array-clone-fixes
Add queue
Implement range change dispatch on Queue
Upgrade Queue to Deque
Implement {peek,poke}{,Back} on Array shim
Document Deque
Optimize Deque push and unshift

Passing arguments as an object to array slice deoptimizes push and
unshift in at least V8 at present. This change rolls that call into a
loop.