Version: Releasing version 2.4.3
Sets Volume to 100% on app launch
Added preference to enable max volume on start (opt-in)
Merge branch 'master' of https://github.com/DroidPlanner/droidplanner.git into issue_375

Conflicts:
	Android/res/values/preferences_keys.xml
Merge pull request #838 from squilter/issue_375

Implemented optional max volume on start (Issue 375)
added unit tests run as part of the gradle build process.
commenting out failing unit test to pass the travis ci build process.
Merge pull request #839 from DroidPlanner/feature_ci_unit_tests

Travis CI unit tests validation
Refactor preference to the DroidplannerPrefs class.
Merge pull request #840 from arthurbenemann/refactorVolumePreference

Refactor preference to the DroidplannerPrefs class.
Bugfix: Use correct method to check the volume preference
Merge pull request #841 from arthurbenemann/refactorVolumePreference

Bugfix: Use correct method to check the volume preference