Enable markdown table rendering, improve docs

Enable Redcarpet markdown table rendering in the MarkdownHelper. Also
improve the docs for MarkdownHelper and don't do unnecessary type
coercion as render_markdown method should only accept a String.
Add a verification state column to cookbook_versions
Show a verification overview in the metrics API
Update chef-legacy to 1.3

The ongoing data migration will not process tarballs which appear to be
invalid, and will report the errors it finds to Sentry
Improve search results responsiveness

Follow button no longer wraps on mobile displays. Make sort buttons 100%
width on smaller displays.
Merge pull request #474 from opscode/markdown-tables

Enable markdown table rendering, improve docs
Merge pull request #476 from opscode/cookbook-versions-import-verification

Add column to cookbook_versions to support README/dependency migration verification
Load either .env or .env.production on boot

This will allow us to change the Supermarket cookbook to symlink its
.env template to .env.production. Once that's in place, we should be
clear to make dotenv the sole mechanism of configuration.
Merge pull request #475 from opscode/chef-legacy-1.3.0

Update chef-legacy to 1.3
Display cookbook version as cookbook updated at

Since publish version doesn't update a cookbook we should display the
created at date for the latest version to represent when a cookbook was
updated.
Merge pull request #477 from opscode/follow-button-responsiveness

Improve search results responsiveness
Merge pull request #481 from opscode/display-actual-updated-at-date

Display cookbook version as cookbook updated at
Update content when managing profile agreements.

When a user is logged in and managing their profile, display the dates of the
agreements as well as more descriptive button text.
Display flash notices below beta banner.

In order to raise visibility of flash messages, move them below the beta banner.
Redirect (re)signing of CCLA to Contributors tab.

When a user signs or resigns a CCLA, redirect them to the Contributor
invitations tab.
Redirect user to signature list after signing ICLA

After a user has signed or re-signed an ICLA, redirect them to the list of individual
contributors (currently the Contribute menu nav item). This removes any
confusion dealing with resigning or refilling out the form.
Update non-admin CCLA signature view text.

In the manage profile agreements tab, update the language surrounding viewing
the CCLA signature content. Eventually, this should be changed to view
Organization or view Contributors where the user can view the other members of
that organization instead of the form to update the signature.
Display information about re-signing an ICLA.

When viewing an ICLA, display information surrounding what it means to resign
the ICLA and when it was originally signed.
Remove company column and adjust name display in sigs list

Remove the company column displayed in the table of ICLA signatures.

When viewing the list of ICLA signatures on production, there appear to be some
blank names. Using the first and last name (required fields of the signature)
ensures that it will not be blank.
Change Approved Contributors copy to Contributors.