increment version

increment version of zimlet

Update README.md

Update groupcal-installer.sh

* Fixed handling of multi-day appointments

* Fixes for 8.6

* Fixup for recurring appointments disappearing

* Optimized table drop

* Groupcal included a way of removing appointments out of the request…

…ed sync window. This, however, resulted in the fact, that deleted appointments wouldn't be deleted from the database. To simplify, we simply drop and rebuild the table now.

* Added SQLite JDBC jar

* Token-Fault on search with multiple pages fixed

* DoS-mitigation wait time added