Apprise notifications (#43)

* issue #4 Adding settings screen for apprise URLS
* Adding test notification mechanism

* Move Worker module to own class file

* Adding basic notification URL runner

* Tests for notifications

* Tweak readme with notification info

* Move notification test to main test_backend.py

* Fix spacing

* Adding notifications screenshot

* Cleanup more files from test

* Offer send notification test on individual edits and main/default

* Process global notifications

* All branches test

* Wrap worker notification process in try/catch, use global if nothing set

* Fix syntax

* Handle exception, increase wait time for liveserver to come up

* Fixing test setup

* remove debug

* Split tests into their own totally isolated setups, if you know a better way to make live_server() work, MR :)

* Tidying up lint/imports

backend/run_all_tests.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+
+# live_server will throw errors even with live_server_scope=function if I have the live_server setup in different functions
+# and I like to restart the server for each test (and have the test cleanup after each test)
+# merge request welcome :)
+
+
+# exit when any command fails
+set -e
+
+find tests/test_*py -type f|while read test_name
+do
+  echo "TEST RUNNING $test_name"
+  pytest $test_name
+done