version 0.3.5-alpha

enhancements:
- don't show calendars/address books in account when no calendars/address books were added

bug fixes:
- select only events from correct calendar when querying (fixes #37)
- ignore non-OK values in multi-status response (fixes #35)
- fix wrong entries in setup calendar/addressbook selection
- commit after every 100 resource downloads to avoid TransactionTooLargeException
- don't delete resources without file name (fixes #33)
- avoid crashes when content providers return null cursors
- ignore invalid URLs (for instance, with spaces) in WebDAV multi-status responses