Store session in the database

Issues
-------
- Closes #68

config/environments/production.rb

@@ -46,7 +46,7 @@
   # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
 
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
-  config.force_ssl = true
+  # config.force_ssl = true
 
   # Include generic and useful information about system operation, but avoid logging too much
   # information to avoid inadvertent exposure of personally identifiable information (PII).