Restructure and rename files as discussed in Slack

[Sjmarf]

[Sjmarf]

I think Slack has eaten that conversation now; iirc the gist was:

• Views that are a navigation page should be suffixed with Page rather than View
• Views that are used in only one parent view should be defined in an extension of that view. All others should be in a Components folder
• All pages should be in a folder of the same name, along with any of their extensions. All page folders should be in a folder called "Pages"

[EricBAndrews]

This is going to cause a massive headache for any in-flight PRs, so we should do this dead last once we've got our 2.0 codebase in order

[Sjmarf]

We plan to try refactoring into packages (like Ice Cubes does) post 2.0 release

[EricBAndrews]

I've split this out into sub-issues to be easier to track