Using cal10n-api: fix SupportedSourceVersion compilation warning

[Sylvain-Bugat]

When using cal10n-api this compilation warning is displayed: [WARNING] Supported source version 'RELEASE_5' from annotation processor 'ch.qos.cal10n.verifier.processor.CAL10NAnnotationProcessor' less than -source '1.7'

This workaround has been found on netbeans and another projetct bug tracker: https://netbeans.org/bugzilla/show_bug.cgi?id=210286 https://github.com/kohsuke/metainf-services/issues/3 They have the same warning.

This warning will not be fixed in the java compiler by a -Xlint option because this behaviour is expected and documented: https://bugs.openjdk.java.net/browse/JDK-8037955 https://bugs.openjdk.java.net/browse/JDK-7184902

[merusso]

This is a really annoying issue that needs to be fixed!

However, I'm not sure about this specific fix. What would happen if Java 9 was used. Will this warning be output? What if instead, the "latestJavaVersion" was used? Then the warning should never be output.

[MartyIX]

This bug seems to be reported also here: https://jira.qos.ch/browse/CAL-47

[Deathnerd]

Any movement on this would be appreciated. We have an slf4j dependency and get this compilation message multiple times throughout the build. It doesn't break anything but it is annoying