This updates the default AWS default symbol to include a space after the
symbol to make it a little bit more readable. Have also updated the
README to include the AWS module.
Implements the Default trait for SegmentConfig to clean up construction of empty segments.
Also adds a segment::new() function to ease construction of simple segments.
Given the global nature of the Kubernetes module, the module has been disabled by default. The opportunity has also been taken to refactor the Kubernetes module to use the new config module.
