This commit includes the major changes between DAVdroid and EteSync. It
adjusts the app to use the EteSync protocol and server. It includes some
ugliness still, and it's a squash of many ugly snapshot commits while
hacking on the initial DAVdroid code.
History should be "clean" from this point onwards.
* AccountDetailsFragment: at account creation, enable task sync only when OpenTasks is installed
* PackageChangedReceiver: when packages are (un)installed, check for OpenTasks availability and (de)activate task sync for all accounts accordingly
* LocalTaskList: don't cache OpenTasks availability
* sync_*.xml: don't activate sync by default
* share debug info: always use attachment (before: send inline if it was small enough)
* use FileProvider for debug info attachment (for Android 7 compatibility)
* dav4android, ical4android fixes
* use cert4android instead of MemorizingTrustManager
* new app setting: distrust system certificates
* add network security config to manifest so that user-installed CAs will be accepted in Android 7 again
* update gradle
* rewritten contact group support to support VCard3 CATEGORIES and VCard4-style KIND/MEMBER groups
* new account setting: contact group method (VCard3/VCard4/Apple "VCard4-as-VCard3")
* keep unknown properties when saving/generating VCards
* increase target API level to 23 (Android 6), which makes Android 6-style permissions mandatory
* AUTHENTICATE_ACCOUNTS permission is only required up to API level 22
* new activity: PermissionsActivity which shows missing permissions and provides buttons to request them
* DavService: Android shouldn't send a null Intent, but sometimes it does, so implement null check
* LocalTaskList: tasksProviderAvailable may return true on API level 23+ even if permissions are not sufficient
* SyncAdapterService: show a notification (with Intent for PermissionsActivity) when permissions are not sufficient
* when creating accounts, set OpenTasks sync always to true if API level is 23+ (even if OpenTasks is not installed [yet])
* update Lombok
* new setting: only sync in WiFi (or when sync is triggered manually)
* new setting: only sync in specific WiFI (by SSID)
* lower default sync interval when account is created to 4 hours (was 1 day)
* version bump to 1.0.6
* re-initialize logger in :sync process after changing the settings (IPC using broadcast)
* move settings from SharedPreferences (which is not multi-process-safe) to ServiceDB
* logger: show exception details
* settings: show debug info
* add startup dialogs (F-Droid: donations, Play Store: DRM bug, OpenTasks not installed)
* allow to reset hints/startup dialogs
* AccountSettings: fragment as inner class of activity
* add account setting + GUI: restrict time range in the past
* add support for restricted time range VEVENT synchronization
* fix bug in handling changed exceptions of recurring events
* use ExternalFileLogger to log synchronization, if enabled in Settings
* new settings: log to external file / log verbose
* DavResource: check for well-known even if service type of user-given URL can't be determined
* remove oblsete testing assets
* move address book settings from account user data to ContactsContract.SyncState
* remove "VCard4 capable?" setting (as it's detected at every sync)
* show user notification when updating settings version or when Android version was increased
* improve stack trace in DebugInfoActivity
* get rid of Guava (use Commons again)
* remove VJOURNAL/notes sync (will be implemented later)
* setup: add "install Tasks app" fragment
* version bump to 0.8.0-beta1
* use Tasks instead of Mirakel
* handle task list colors
* allow independent selection of calendar/task sync for the same CalDAV calendar
* minor refactoring (don't use return value of Builder)
* handle more task fields and time zones
* sync interval setting for tasks
* account settings: show whether CardDAV server supports VCard 4.0
* CardDAV GET: ask for VCard 3.0 or VCard 4.0 (preferred) contacts
* CardDAV multiget: ask for VCard 4.0 contacts if the server supports it
* CardDAV PUT: send VCard 4.0 contacts if the server supports it
* import Apache httpclient-android rev. 1652769 correctly (hopefully fixes#491)
* new Settings activity
* Settings: display/change user name, password, preemptive auth.
* Settings: display/change sync. interval for contacts and calendars
* requires permission GET_ACCOUNTS to list accounts in Settings
* requires permission READ_SYNC_SETTINGS to display current sync intervals
* remove obsolete files from res/
* update copyright notices
* version bump to 0.7
* remove debug settings activity; logging can now be enabled via adb setprop, since that's the default way of enabling verbose logs in HttpClient's Android flavour and adb is required for viewing the logs anway
* update i18n accordingly
* moved all dependencies to gradle instead of shipping .jar files in the app/lib directory
* switched to official Android port of HttpClient instead of httpclientandroidlib
* new .gitignore and project files