getEvents_internalOld removed from EventManager
getAllowedSpaces() added to CalendarService
constants added for Event class
EventManager changed from hql to lucene search
getQuery() removed from EventsManager
unnecessary requirements removed
Merge remote-tracking branch 'origin/dev' into lucene-search

Conflicts:
	src/main/java/com/celements/calendar/manager/EventsManager.java
testGetSize() added to EventSearchResultTest
EventSearchTest implemented
Delegations added to deprecated methods in CalendarUtils
XWikiDocument parameters changed to DocumentReference in CalendarService
unit tests for getAllowedSpaces() and getAllowedSpacesHQL() implemented
in CalendarServiceTest
unit tests for getEventSpaceForCalendar implemented
in CalendarServiceTest
changed XWikiDocument in to DocumentReference in EventsManager
EventsManagerTest fixed an expanded
calling EventSearchResult.getEventList() with limit = 0 now returns all
remaining events instead of none
updating celements-core to 1.50-SNAPSHOT
using getRefDefaultSerializer() and getRefLocalSerializer() from
IWebUtilsService
CalendarService.getAllowedSpacesHQL(DocumentReference) method due to
deprecation and no usage
CalendarEngineHQL and CalendarEngineHQL implemented