Add application/postscript to the list of valid tarball content types

This is required in order to migrate all cookbooks from the Opscode
Community Site.
Link user stats to corresponding tab

User stats now link to the corresponding tab on the user profile,
complete with link hover states.
Improve cookbook search

To provide better search results based on name this weights cookbook
name and maintainer over cookbook description.
Merge pull request #469 from opscode/add-postscript-to-valid-content-types

Add application/postscript to the list of valid tarball content types
Merge pull request #470 from opscode/link-user-stats

Link user stats to corresponding tab
Merge pull request #466 from opscode/optimize-search

Improve cookbook search
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
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
add /universe endpoint
remove oj
switch to redis for caching
platforms aren't used
add location_type and location_path
remove platforms from cookbook_versions too
adjust ruby style
fix a failing spec
appease rubocop