Port to libecal-2.0
Once evolution-data-server#33 (closed) lands, please review and merge these changes. They also removed usage of the deprecated functions mentioned in #1 (closed), but didn't revert the change for the #1 (closed).
Once evolution-data-server#33 (closed) lands, please review and merge these changes. They also removed usage of the deprecated functions mentioned in #1 (closed), but didn't revert the change for the #1 (closed).