Adjust build to new Sonatype architecture (Maven Central)

[MenoData]

Due to a big change of Sonatype architecture for publishing to Maven Central an adjustment to local build procedure is needed in all Time4J-components. Proposal as recommended by Sonatype: Use the new plugin "central-publishing-maven-plugin". See:

Plugin-Documentation

[MenoData]

New build works fine (in deploy mode - running mvn deploy) for TZDATA (helped to publish new timezone version v2026b). Now the other components like Time4J-Base etc. need the same update.