ensure all about.html and license.html files are included via build.properties in the feature; ensure all features contain some license info (be it license.html or embedded in feature.xml/feature.properties)

Just noticed that jst/features/org.jboss.tools.jst.feature/build.properties only includes feature.xml and feature.properties, but omits its about.html file.

We should ensure that all features properly include all their about/license files.