Organizations index should be CclaSignatures json index

Since organizations index actually returns CclaSignatures what is now
the organizations index should be the json format of the
CclaSignaturesController. This also adds the CclaSignature.by_organization
scope so the CclaSignatures returned are unique by organization, this
should resolve any current confusion surrounding this feature.
Admins can accept requests to join their organization
Tools can be deleted

Tools can be deleted by tool owners or supermarket admins.
Fix heading with button CSS bug

The buttons have a weird CSS transition, remove it, and the buttons on
the tools view aren't flowing correctly, fixes it.
Admins can decline requests to join their organization
Merge pull request #612 from opscode/respond-to-requests-to-join-organizations

Admins can respond to requests to join their organization
Merge pull request #615 from opscode/delete-tool

Tool deletion
implement the show page for tools
Don't track API downloads in Segment.IO
Refactor much of cookbook SCSS into resource SCSS

A lot of the cookbook show SCSS can be reused for tools and plugins so
this moves it into a wrapper class called resource.
Order other users tools by name
Merge pull request #620 from opscode/combine-org-qa-fixes

Organizations index should be CclaSignatures json index
Merge pull request #611 from opscode/tool-show-view

implement the show page for tools
Merge pull request #621 from opscode/dont-track-api-downloads-in-segment-io

Don't track API downloads in Segment.IO
Ensure Curry Repository attributes are not null

This enforces non-nullable Curry::Repository attributes at the database level.
Merge pull request #622 from opscode/not_null

Ensure Curry Repository attributes are not null
ApplicationController always 404s with HTML
Handle missing templates with 404s
Merge pull request #623 from opscode/missing-template-exceptions

404 with HTML by default
Return descriptive errors from bad cookbook uploads.