Add logging to example config

Author: yhabteab

config.example.yml

@@ -16,3 +16,24 @@ database:
   user: noma
   database: noma
   #password: noma
+
+logging:
+  # Default logging level. Can be set to 'fatal', 'error', 'warn', 'info' or 'debug'.
+  # If not set, defaults to 'info'.
+  #level: info
+
+  # Logging output. Can be set to 'console' (stderr) or 'systemd-journald'.
+  # If not set, logs to systemd-journald when running under systemd, otherwise stderr.
+  #output:
+
+  # Interval for periodic logging defined as duration string.
+  # A duration string is a sequence of decimal numbers and a unit suffix, such as "20s".
+  # Valid units are "ms", "s", "m", "h".
+  # Defaults to "20s".
+  #interval: 20s
+
+  # Map of component-logging level pairs to define a different log level than the default value for each component.
+  options:
+    #database:
+    runtime-updates: info
+    #listener: