Cleanup (#820)

* Update instructions and readmes
* Cleanup in base files
* Cleanup in core files
* Cleanup in gui files
* Cleanup in dialog files
* Cleanup in tools files
* Cleanup in test files

tests/conftest.py

@@ -143,7 +143,7 @@ def fncConf(fncDir):
 
 
 @pytest.fixture(scope="function")
-def dummyGUI(monkeypatch, tmpConf):
+def mockGUI(monkeypatch, tmpConf):
     """Create a mock instance of novelWriter's main GUI class.
     """
     monkeypatch.setattr("nw.CONFIG", tmpConf)