Refactor allowed_keys method as a class variable
Method does not perform any computation or modify data as it is a static
tuple, therefore it is better expressed as a class variable.
* Set encoding on open call in setup.py
If a host OS does not have a UTF-8 locale set the read() call is unable
to read the utf-8 encoded README.rst file.
* Remove non-ASCII characters from README.rst
Allows for running behave tests with an alternative base image
than the official postgres image.
Also provides a PG_USER/PG_GROUP should that be different to the
default `postgres`.
Fix issue of patroni configuring watchdog with defaults when bootstrapping a new cluster rather than taking configuration used to bootstrap the DCS.
Also log changes to watchdog configuration based on calculated timeout value.
Close#2470
