A big pile of refactoring

[k-stewart]

• Move PhantomJS logic into its own files, so we can easily swap it out with something else
• remove unused methods
• separate concerns
• split multi-concern files into single-concern files
• use class << self when there are more than one class method
• simplify a bunch of if trees and case switches
• remove some unnecessary cross-object dependencies
• DRY up duplicated logic
• use .map instead of .each when the only goal is to push things to an array

[k-stewart]

Tagging @wioux and @j-ro as people who might have opinions about these changes; feel free to unassign yourselves

[j-ro]

We're pretty behind the master branch and don't generally keep up (and I'm not a developer exactly myself), so I don't have many opinions. I'd just say please keep the documentation updated as to any changes in the front-facing API (rake tasks, etc...).

[k-stewart]

Will do.