Introduce Tomcat internalProxies/trustedProxies and AccessLogValve's requestAttributesEnabled properties

Looking to standardise the Load Balancer configuration on Atlassian Docker Images, I propose a change to configure the following Tomcat properties by using environment variables:

Both trustedProxies and internalProxies require IP addresses with escaped dots, so ideally a new logic on entrypoint_helpers.py needs to parse the declared IP addresses for consistency.

For requestAttributesEnabled, it can be assumed as false by default.