Create EventService class
create EventService class
Add EventService
Fix EventService
Fix Alarm
Update code version
Add #45 feature
Fix Design
Merge branch 'Design' into alpha

Conflicts:
	AndroidManifest.xml
	res/layout/activity_event_add.xml
fix design
improve design
Add period end date picker
Improve EventChecker
change error messages
refactor services
Fix EventAlarm getNextOccurrence method
update code version
add preferenceActivity
delete unused includes
unlock screen