Re #2976 Allow `id` values to be generated from a function given attrs
pass along model and comparator to cloned collection. Fixes #3013
Merge pull request #3032 from akre54/clone-opts

Pass along model and comparator to cloned collection
Merge pull request #2985 from caseywebdev/generate-id

Re #2976 Allow `id` values to be generated from a function given attrs
#2985 -- use 'change-id' as the event name
Change the reference to rails in the 'sync' docs to reflect Rails 4
Merge pull request #3037 from rsofaer/update-docs-rails-4

Change the reference to rails in the 'sync' docs to reflect Rails 4
Update collection docs on underscore methods.
Merge pull request #3040 from braddunbar/underscore-methods

Update collection docs on underscore methods.
Fix #3015 - History#stop cleans up iframe.
Merge pull request #3041 from braddunbar/iframe-cleanup

Fix #3015 - History#stop cleans up iframe.
Return `id` assumption for simple polymorphic `Collection#model` factories.

Also, add tests to make sure it doesn't break in the future.
Make new tests more thorough
remove un-used local variables
Merge pull request #3053 from sfishel18/master

Remove un-used local variables
Update devDependencies

PhantomJS fixed the really annoying "CoreText performance note:" message in
1.9.3 or so.
Merge pull request #3054 from caseywebdev/deps

Update devDependencies
Automatically rewritten for npm.