ph-css 8.0.0

• Requires Java 17 as the minimum version
• Updated to ph-commons 12.0.0
• Removed all deprecated methods marked for removal
• Removed the separation between CSS2 and CSS3 - all one now
• Removed class ECSSVersion and interface ICSSVersionAware because they have no real role anymore

Full Changelog: ph-css-parent-pom-7.1.0...ph-css-parent-pom-8.0.0