Docs: Document how logging works in dodal

[DominicOram]

As a dodal user e.g. a DAQ person writing an application or a beamline scientist playing around I would like to know how to set up logging.

Currently this can be done by just calling:

from dodal.log import LOGGER, do_default_logging_setup
do_default_logging_setup()
LOGGER.info("hello world")

Which will set up some defaults for you, including logging to graylog at https://graylog.diamond.ac.uk/streams/662655e6b17cec581f3cf46d/search. We should document:

• The default locations it puts text logs
• Debug logs and the CircularMemoryHandler
• How to override these defaults
• Recommended tags to add to the logs and how to add them