This commit adds a workaround for sync apps which don't grant account visibility to OpenTasks. If a task list is inserted which belongs to an account which we can't see, the app asks for permission to see the account.
The `GET_ACCOUNTS` permission is no longer used on Android 8+ and the request for that permission will no longer be shown when the app starts.

Update the publish configuration to derive the publishing track form the version number.

In an earlier commit we changed how the lists are loaded. Instead of loading them from the tasks table we now load them from the instances table. This was meant to prepare support for recurring tasks.

Unfortunately we missed on line where we were still using the `_id` column to get the task id (when we should actually use the `task_id` column now). This didn't cause any problem as long as the task id and the instance id where in sync (hence it wasn't an issue while testing). However, under certain circumstances this assumption is no longer true and caused an illegal Task URI to be loaded when clicking a task.

The list now uses the `task_id` column to create the task URI to show.

This adds a plugin which allows for publishing the app autimatically to Google Play.

Adds an optional signing config, which is ignored if no keystore property is present.

This also updates the support library version to 26.1.0.
Due to changes in Android 8 we had to limit some background service and broadcast functionality. There are no limitations to the user experience though, but some planned features may require a different solution now (mostly because implicit broadcasts no longer work).

Commit 5f4e9012 contains a couple of changes which break the UI in that some elements don't respond to clicks anymore.
In particular the `focusable="true"` attribute seems to cause these issues. For now we simply revert the addition of these attributes.
In another story we should address the issue and fix the layout.

This commit switches from using the color picker as an activity via the open intent to using the color picker as a dialog fragment. This means the color picker is fixed now and no external picker can be used. It's not clear if anyone actually did that though.

This adds adaptive icons for Android 8 and round icons for older Android versions which use them.
Also the bitmap icons are now moved from drawable to mipmap.

This solution fixes a number of actual and potential bugs around changing the content of the details pane. The view fragment can be simplified further. That's subject to another story.

javadoc fixes and more

* android lint (accessibility - performance)
* Keyboard inaccessible widget
* ScrollView size
* Use apply() on SharedPreferences
* Obsolete layout params
* android lint (security - code style)
* showAsAction=ifRoom
* code style issues

This commit adds a permission group for tasks. The permission group has a dediciated description which, for most languages, is derived from the write permission description.

@native speakers, please feel free to update these and bring them in line with the default translation.

Improved german translation.

Commit new code style settings file introduce in Idea 2017.3 (Android Studio 3.1 automatically generated these files, migrating the project rules from the old format). #671 (#672)

Use View.peformHapticFeedback() instead of Vibrator.vibrate() for list item long press and checklist long presses so it is enabled/disabled as per device settings. Remove an unused field in FlingDetector. #191 (#660)

Provides much faster builds

See: https://docs.gradle.org/4.4.1/release-notes.html
See: https://docs.gradle.org/4.3.1/release-notes.html
See: https://docs.gradle.org/4.2.1/release-notes.html

Allows Github to find the license and display additional meta
information as well as improving the 'community profile'.

This commit fixes inserting instances to comply with the JavaDoc. In order to achieve that this improves DateTimeArrayFieldAdapter by returning and taking Iterables instead of arrays.

Let instance view return instance DTSTART and DUE rather than the task values. Implements #615 (#620)

This commit improves the instances view by returning the instance start and due times as task `DTSTART` and `DUE`. This way the UI will see the correct instance times.

From the UI perspective the instances view is now a list of individual non-recurring instances, which can be read and written on its own.

Note, for non-recurring tasks, this won't have any effect.

This also changes INSTANCE_ORIGINAL_TIME to use null for non-recurring tasks.

Clean up TaskGroupPagerAdapter instantiation exception handling and some unused code in TaskListActivity. #621 (#622)

This commit adds initial support for operations on the instances table. At present sync adapters are not allowed to write to the instances table, non-sync adapters can only insert or modify task values. Instances table columns are still read-only. Also, columns related to recurrence can not be set via the instances table.
This is meant to simplify working with recurrence in the UI. The UI won't have to take special care about creating exceptions. It can simply update or delete individual instances and the provider will take care of creating overrides or ex-dates.

This also fixes Travis not running the `check` task and improves/fixes the provide tests in general.

This certainly needs to be revisited, but it should be ok for now when it's mostly required to write unit tests.

This commit replaces the `instance_status` column with a more veratile `distance_from_current` which has additional semantics for upcoming instances.

This commit adds an instance status column which indicates which instance of a task is the next one to complete. This allows to filter out the instances which come after the next one.