Qtoggleserver

* Frontend: fixed error when loading app.

version-0.22.0-beta.1
What's new (since 0.21.x):
* Added `{GET,PUT} /system` API calls.
* Added `GET /backup/endpoints` API call.
* Added `PUT /ports` API call.
* Added `PUT /device` API call.
* Added `backup` device flag support.
* Adjusted various API calls to new qToggle API specs.
* Added full support for backup/restore (both server and frontend).
* Many minor fixes.

version-0.21.12

* Frontend: fixed error when logging in as _normal_ or _viewonly_ user.
* Frontend: removed blur effects to reduce performance penalties.

version-0.21.11

* The jinja2-based template rendering mechanism is now fully asynchronous.
* Fixed notification messages missing proper display value when choices are defined.

version-0.21.10

* Core/Expressions: fixed `ROUND()` function.
* Dashes are now allowed in device names.
* Frontend: improved bad experience due to long timeouts when loading UI.
* Frontend/Dashboard: improved port search mechanism.


version-0.21.9

* Frontend: increased max number of decimals to 10 for some widgets.
* Lib/BLE: simplified the return type of some methods.

version-0.21.8

* core/ports: fixed an issue where cached attributes weren't available when handling events.

version-0.21.7