Improved based on reviewer feedback.
Improved based on reviewer feedback.

- Clarified and fixed full ID / calid XCCDF ID concept.
- Removed attempts for XML output indentation, as it is unclear what it does.
- Expanded help of the output argument.

OpenSCAP/openscap,OpenSCAP/openscap,OpenSCAP/openscap,OpenSCAP/openscap,OpenSCAP/openscap,OpenSCAP/openscap