Be less specific when finding existing seed Account

The where clause is too specific for the Account seed data so it tries
to create a duplicate account (and fails) so this makes it less specific
only matching on username and provider.
Add seed data for tools

Add seed data for both knife plugins and ohai plugins (tools).
Refactor cookbook partial SCSS to be more generic

Since the styles for the tools partial are the same as the
cookbook partial this refactors the styles for the cookbook partial so
the class names are more generic so they may be used for tools.
Add tools index

Add a tools index that lists all tools.
Change Tool#user to Tool#owner

For consistency with Cookbook this changes Tool#user to Tool#owner and
adds a convenience method Tool#maintainer that fetches the owners
username.
Support tools atom feed

Support tools atom feed ordered by created at dates.
Support filtering tools by type

Allow tools to be filtered by type based on Tool::ALLOWED_TYPES.
Limit allowed tool types

Limit and validate the allowed type of tools that can be created.
Abstract heading with buttons into common scss

There are now a bunch of places where we have UI with a title and
buttons to the right, this abtracts the cookbooks search styles for that
so it can be reused on the tools directory and user profile.
Fix botched merge conflict.
Fix server side error messages for tool validation

@user needs to be assigned if we're going to render new with @tool with
error messages also need to display the error messages.
Refactor simple cookbook styles to simple listing

So the simple cookbook styles can be reused with tools this refactors
them to simple listing.
Link to tools from the dashboard.
Admins are notified of requests to join their org

Users may only request to join an organization if they are not already
in the organization and if they have not already requested to join the
organization. The actual sending of the notifications happens in the
background because the number of admins an organization has is not
constrained.

The feature spec is marked as pending because the whole feature is not
complete. Once admins can accept (and decline) requests, the feature
will no longer be marked as pending.
The Join Organization feature can be toggled

If the JOIN_CCLA_ENABLED environment variable is set, the feature
appears and is accessible. Otherwise, it is not.
Merge pull request #606 from opscode/request-to-join-an-organization

Users can request to join an Organization's CCLA
Merge pull request #598 from opscode/tools-directory

Tools directory + supporting changes
Create the feature spec for deprecating a cookbook
Create the cookbook deprecate? authorizer.

Cookbook owners and Supermarket admins can deprecate non-deprecated cookbooks.
Implement the Cookbook deprecate controller action

The Cookbook deprecate controller action allows a specified cookbook to be
deprecated and replaced by another cookbook.