Fix cookbook platform and dependency access scope

Accessing these relations through a has_one relation results in
displaying all SupportedPlatform and CookbookDependency models
associated with _any_ version of the cookbook.

This feels like it could be a Rails bug, but for the time being, we can
fix it by adding these two simple methods to Cookbook
Handle no specified cookbook supported platforms.

In the UI, if there are no supported platforms specified for a cookbook, let the
user know.

This displays an icon and tooltip message on the cookbook partial and cookbook show.
Merge pull request #301 from opscode/fix-cookbook-dependency-and-platform-query-scope

Fix cookbook platform and dependency access scope
Merge pull request #302 from opscode/handle_no_cookbook_supported_platforms

Handle no specified cookbook supported platforms.
adding owners and collaborators
adding controllers and specs
adjusting routes and adding specs
use jbuilder for this
add select2 for picking collaborators
stop messing with the routes
users should have icla signatures to be collaborators
make the views work
fixing specs
these are useless
collaborators can remove themselves
put the helper back
fixing specs and rubocop offences
adding a mailer for collaborators
didn't need this
Specify the cookbook owner in the db seeds.

When rake db:seed is run, the owner gets set to the user created in the seeds.
This allows cookbook show to function as expected because a user is required.

The ordering of the seeds changed to have users be created before cookbooks, so
the association could be made.