NB Build: Basic support for javac.release property.

[mbien]

• custom javac and sigtest tasks needed updates
• JarWithModuleAttributes too, which sets the OpenIDE-Module-Java-Dependencies manifest attribute based on the language level
• ant nbm projects (apisupport.ant) needed to be made aware of the javac release property

apisupport.ant of NB 21 loads all projects which use javac.release as java 1.4 projects, if we get this into NB 22 and devs start using the new release, we can start swapping out source/target with release during the NB 23 dev cycle.

[mbien]

all green except paperwork
edit: also fixed

[mbien]

this PR now only contains the changes to the build system and is targeting NB 22. Part 2 for NB 23 would be in #7247

[lahodaj]

Looks sensible to me.

[mbien]

gave this a bit more testing:

• the right bytecode level is produced
• no errors in the editor while using release=17 and jdk 17 API (means that the property is picked up correctly)
• value can be modified using project UI

this however did not work:

• when using JDK 17 API but setting release to 11, the editor did not show the API usage as error even though the build fails

this likely indicates that the editor is using source still. I have to take another look if I can implement this too, however even if not I think we should merge this as first step.

[lkishalmi]

I think it's Ok to merge, and fix the API usage later on. It affects the module developers only. Speaking of me I can live with that.

[mbien]

I tracked it down to this which returns null:

netbeans/java/java.source.base/src/org/netbeans/modules/java/source/parsing/JavacParser.java

Line 960 in 8cc5215

String useRelease = useRelease(sourceLevel, validatedSourceLevel);

netbeans/java/java.source.base/src/org/netbeans/modules/java/source/parsing/JavacParser.java

Lines 1098 to 1100 in 8cc5215

	if (validatedSourceLevel.equals(sourceLevel)) {
	return null;
	}

because validatedSourceLevel is the same as the requested source level. If I let it return the requested source level instead of null, the javac task will set relaese and there will be error badges, however this causes exceptions somewhere else.

Lets not do that. Going to merge, thanks for the reviews.