Document CSS with Knyle Style Sheets (KSS)

 * Component tooltip
 * Component fetch
 * Bootstrap overrides
 * Section search
 * Section tags
 * Shared layout
Refactoring and Optimization

 * Use Devise user_session helper in favor of directly accessing warden session
 * Refactor MyGists::Fetch::Options#since
   * Return the last updated gist's timestamp advanced by one second, so
     the last updated gist will not be included in response from GitHub API
 * Add index on tags.name
 * Add index on gists.updated_at
 * When searching:
   * Only get a Profile when profile search term is a string and present
   * Eagerly load gist profiles
 * Add redis-rails gem
 * In production, configure rails to use redis as cache store
 * For redis cache store, set redis DSN with environment variable
 * Add MyGists::Cache to read and write cache entries
 * Add rake task cache:write for writing caches for search form
 * In SearchController, expose tags and profiles via MyGists::Cache