* Implemented new dark theme
Now uses a dedicated css file for all dark theme color changes, rather
than replacing color codes directly.
Color theme is from discussion in #60.
* Minor link color update
Basic autocomplete/search suggestion functionality added
* Adds new GET and POST routes for '/autocomplete' that accept a string query and returns an array of suggestions
* Adds new autoscript.js file for handling queries on the main page and results view
* Updated requests class to include autocomplete method
* Updated opensearch template to handle search suggestions
* Added header template to allow for autocomplete on results view
* Updated readme to mention autocomplete feature
Added <meta name="referrer" content="no-referrer"> to all whoogle
templates
Refactored search route to use conditionally use either request.args or
request.form, depending on rest call (get vs post respectively)
