This removes the WorkerThread class and many of the complications around it.
Instead of having a generic worker, there is now the `QueueRunnerService` which takes on all the resposibilities for handling queued tasks.
This is one step towards removing `FIXMEGlobal`
The new API avoids using HTTP status codes and verbs.
Added new structure for having a similar response envelope and pagination support for V2 calls.
Added extensions to the systemInfo call so the client knows if the V2 methods are available.
This moves the throttle support to the StreamUtil throttled stream, which allows multiple streams to share a throttle value, such that the throttle setting is applied to the entire communication from Duplicati, and not for each connection.
This also cleans up a bit in the progress reporting, where the backend manager now keeps track of the "active" transfer and only emits progress on that. Once it finishes, a new transfer is promoted a "active".
* Simplified task control by having all logic in a single class and using async control mechanism
* Fixed the tests
* Made the marking of a backup partial explicitly communicated if the enumeration process is stopped.
* Added support for pausing active transfers
* Introduced transfer token to abort operations.
* Updated the way LiveControl is emitting events.
* Retains the paused state of the server across reboots, this fixes#5760.
* Reworked the way throttle speeds are propagated through LiveControls.
* Added option to pause transfers in the UI.
* Removed throttle settings from the LiveControls class so it is exclusively handled by the ApplicationSettings.
* Removed `thread-priority` as it does not work at all when tasks are used.
* Fixed the stop dialog and API to only support stop and abort.
* Removed unused variables
Kenneth Skovhede