Fix java -jar saga-site.jar
Fix java -jar saga-site.jar

Sagan is using AsciidoctorJ and JRuby; in order to run, those JARs need
to be unpacked when running with the fat JAR application.

This is why we need to `requiresUnpack` both artifacts.

See:
http://docs.spring.io/spring-boot/docs/current/reference/html/build-tool-plugins-gradle-plugin.html#build-tool-plugins-gradle-configuration-options

fixes #612 for good

dsyer/sagan,spring-io/sagan,spring-io/sagan,spring-io/sagan,martinlippert/sagan,martinlippert/sagan,TabberGit/sagan,dsyer/sagan,TabberGit/sagan,dsyer/sagan,spring-io/sagan,dsyer/sagan,martinlippert/sagan,martinlippert/sagan,TabberGit/sagan,TabberGit/sagan