Refactor require-tree to not share messages

- Pass in messages to each method so they are not shared
- Export each method for calling individually
- Update reference to default export of require-tree
- Add default values for messages if not passed in
Fixing typo in allowedSections for allowed pages under settings
Merge pull request #2311 from stenehall/master

Fixing typo in allowedSections for allowed pages under settings
Prevent settings page from rendering same page twice

Closes #2316
- There was a check to prevent rerendering of same content pane but it wasn't working
- Fixed the check for this
Use tag as title on tag pages

closes #2328
- added check for tag in coreHelpers.meta_title and use if set
- added test for correct title on tag pages

Rewritting to tag - blogtitle based on comments from PR
Merge pull request #2329 from stenehall/master

Fix for #2328 - Added check for tag for title
Merge pull request #2317 from shashankmehta/settings-rendering-issue

Prevent settings page from rendering same page twice
Merge pull request #2292 from jgable/requireTree

Refactor require-tree to not share messages and export parsePackageJson
Change validation for posts 'page' attribute.

issue #2305
- changed validation for 'page' to expect '0' or '1', rather than 'true' or
  'false'
- Added a 'can change a post to static page' test
- Added a 'can change a static page to a post' test