S allius/issue398 (#406)

* setup logger for hypercorn and dashboard

* use logger.ini to setup dashboard logger

* workaround: restore the hypercorn logger config

- quart/hyercorn overwrites the logger config.
  as a workaround we restore the config at the
  beginning of a request

* fix the hypercorn log handler only once

* change proxy into a ASGI application

- move Quart init from server.py into app.py
- create Server class for config and loggin setup
- restore hypercorn logging configuration after
  start of Quart/Hypercorn

* move get_log_level into Server class

* define config in test_emu_init_close

* remove Web() instance from the testcase

- with importing app.py The blueprint Web() will
  automatically created and a second call in test-
  cases must avoided

* add unit tests

* move code from app.py into server.py

* test the init_logging_system() method

* add HypercornLogHndl tests

* fix deprecated pytest async warning

- Cleanup pending async tasks
- fix deprecated warning about event_loop

* add unit test for error handling in build_config()

* coverage: ignore quart template files

* check print output in test_save_and_restore

* update changelog

app/tests/cnf/invalid_config.toml

@@ -0,0 +1 @@
+mqtt.port    = ":1883"