Rspec3 Updates: Spec Syntax, Generators, and Monkey-Patching (continued)

[codebycliff]

Description

This branch continues the work started in https://github.com/drapergem/draper/pull/692. My plan is to fix the conflicts and extract out / revert any unrelated changes.

Testing

Run the test suite.

To-Dos

• [ ] tests

References

• Initial pull request