Prepare for adaptive ui / Switch to libhandy-1
This MR should lay the groundwork for !134 (closed) by
- Cleanup code for unused views (day, list, and search never existed)
- Make GcalWindow inherit from HdyApplicationWindow
- Use HdyHeaderBar instead of raw GtkHeaderBar
To make this possible we switch to the new version of libhandy.
Edited by Evangelos Ribeiro Tzaras