Partially revert f8d8f7d.

Need `${dist.dir}/lib/scala-partest.jar` for maven publish.

We still don't want to distribute it in the distribution,
but will have to remove it in release script, as 2.10.x's
build hasn't been refactoreded like master's, and I'm not backporting it.

Author: adriaanm

build.xml

@@ -1837,6 +1837,7 @@ TODO:
     <copy toDir="${dist.dir}/lib">
       <fileset dir="${build-pack.dir}/lib">
         <include name="jline.jar"/>
+        <include name="scala-partest.jar"/> <!-- needed for maven publish -->
         <include name="scalap.jar"/>
       </fileset>
     </copy>