Bump version to 0.5.8.1, ignore VCards without VEVENTs (fixes #178)
Update strings.xml
Update strings.xml
French translation
French translation that compiles
Support for read-only calendars (closes #126)

* relevant RFCs go into the doc/ directory for reference purposes
* read-only calendar collections are set as read-only in Android
* HTTP exception refactoring to mark 4xx HTTP errors as hard sync errors (numAuthExcetions/numParseExceptions) for Android sync manager
* query current-user-privilege-set for resources, detect read-only resources
* show read-only resources as read-only in SelectCollectionsFragment
* minor refactoring (DavProp.*)
Version bump to 0.5.9

* GUI changes for read-only collections (new icons)
* require only bind, unbind and write-content privileges
Fix a bug that deletes entities remotely even if they have changed remotely (closes #197)
Correct icon sizes to match Android iconography; translations
Merge from upstream
Enable gradle build