2.1 Cleanup

Version 2.0 was released with a few things not quite working exactly how I'd like them to. So, in version 2.1, I'd like to take care of a few of those. This will serve and the 2.1 road map and will be updated as items are completed.

##### Testing

- [ ] Choose an appropriate testing framework/library
- [ ] Write some tests (not shooting for 100% coverage in this release)
- [ ] Write some grunt tasks to automate testing during development

##### Misc

- [x] Bring back the ability to store container element
- [x] Add ability to use a css selector to find dom elements
- [x] Add third-party selector engine support
- [x] Upgrade all hard dependencies to latest versions