Upgrade to the new APIs

The goal is to get rid of all the deprecations. 

### TODO

* [x] Make buffer find specs pass on new space-pen
* [x] Make project find specs pass on new space-pen
* [x] No deprecations in buffer find
* [x] No deprecations in project find
Does space pen view still have `@element` as an alias for `@[0]`? Mind be nicer to use that instead of `this[0]` now.