About Page Tests

Closes #4508

Tests for:

- Version number is a number
- Database type is an allowed 1 of 3
- There are 20 contributors
- First contributor has an image tag and image src exists, alt tag, title tag, href to github
Move testem.json into client tests directory.
Merge pull request #4587 from jaswilli/testem

Move testem.json into client tests directory.
Merge pull request #4579 from PaulAdamDavis/about-tests

About Page Tests
Update syntax in ember templates.

No Issue.
- Outlet names must be quoted.
- {{#each}} helper will no longer implicitly switch context.
  Change usage to {{#each foo in bar}}.
Merge pull request #4594 from jaswilli/ember19-prep

Update syntax in ember templates.
Change sitemap root location

Closes #4590

- Removes `-index` from the root sitemap
- Removes redirects (which send sitemap.xml to sitemap-index.xml)
- Adjust tests
Merge pull request #4599 from PaulAdamDavis/sitemap-index

Change sitemap root location
allow re-login when authorization fails on editor.edit route
minor cleanup after rebase.