rename ravenlog to krowlog

There is a database named RavenDB.
KrowLog starts with a K, which is a) distinctive and b) has an association to KDE.

src/pluginbase.py

@@ -0,0 +1,6 @@
+from PySide6.QtCore import QObject
+
+
+class PluginBase():
+    def __init__(self):
+        pass