Refactorings.
Added Will DTO for MQTT connection loss signalisation.
Moved WillDTO to correct package.
Improved app resiliency.
Handling for connection loss (MQTT).
Made sensor listening operations in service non-blocking.
Added floating action buttons (material design),
Refactorings.
Added basic unit tests.
Merge pull request #18 from rgreschner/development

Merge dev (20141224-1)