* Event class finds and processes exceptions of recurring events
* workaround for iCloud and other services that provide RECURRENCE-ID as DATETIME even if the original event is an all-day event
* VEvents are generated with all time zone definitions (including time zone definitions of exceptions)
* added SQL filter possibility to generic LocalCollection
* added exceptions of recurring events to Event
* process exceptions of recurring events in LocalCalendar
* new Settings activity
* Settings: display/change user name, password, preemptive auth.
* Settings: display/change sync. interval for contacts and calendars
* requires permission GET_ACCOUNTS to list accounts in Settings
* requires permission READ_SYNC_SETTINGS to display current sync intervals
* remove obsolete files from res/
* update copyright notices
* version bump to 0.7
* moved all dependencies to gradle instead of shipping .jar files in the app/lib directory
* switched to official Android port of HttpClient instead of httpclientandroidlib
* new .gitignore and project files