chore(style): code cleanup
fix(balls): ball number can not go below 0
refactor(collection items): Collection items indexes are int
test(change detector): re-add a previously failing test
Merge remote-tracking branch 'misko/change-detector' into animate
chore(whitespace): Fix whitespace in no_animate
docs(Scope): adding documentation
chore(scope): clean up style / remove $
chore(animate): Cleanup.
refactor(NgAttachAware): wait until all bindings fire.

This changes the behavior in that it will wait for one time
bindings to resolve before calling attach();
feat(scope): Experimental: Watch once, watch not null expressions

This is an experimental feature, and may not get into v1.0. Depend
on with caution.
fix(animation handle): Prevent schedule microtask from failing tests.
Merge remote-tracking branch 'misko/change-detector' into animate
fix(tests): All existing tests now pass.
feat(animate): Angular NgAnimateModule.noAnimate() is the default installed module.

To enable animation, you now .
feat(animate): Add tests and test stubs.