* First implementation of search using elasticsearch with facets
* Updated notebook search form to make use of ElasticSearch
* Removed unnecesary custom filters now that ElasticSearch handles that
* PEP8 compliance
* SearchForm now uses new field and form names
* PEP8 compliance
Merge branch 'feature/haystack_demo' into develop

* feature/haystack_demo:
  * SearchForm now uses new field and form names * PEP8 compliance
  * Removed unnecesary custom filters now that ElasticSearch handles that * PEP8 compliance
  * Updated notebook search form to make use of ElasticSearch
  * First implementation of search using elasticsearch with facets
Merge branch 'develop' of github.com:SoloTodo/solonotebooks into develop

* 'develop' of github.com:SoloTodo/solonotebooks:
  * Changed requirements: ** PIL => Pillow ** Added uWSGI * Fixed auto-generation of secret key * Fixed condition to show debug toolbar sidebar