Latest version of org.specs2:specs2-matcher-extra_2.12.0-RC1
https://javadoc.io/doc/org.specs2/specs2-matcher-extra_2.12.0-RC1
Current version 3.8.5-20160914090233-50e99f0
https://javadoc.io/doc/org.specs2/specs2-matcher-extra_2.12.0-RC1/3.8.5-20160914090233-50e99f0
package-list path (used for javadoc generation -link option)
https://javadoc.io/doc/org.specs2/specs2-matcher-extra_2.12.0-RC1/3.8.5-20160914090233-50e99f0/package-list