Show be more verbose when running partest on Jenkins

Enables printing of diffs after test failure and a more summary in the end of test suite.
Diffs do not work yet #609

Author: DarkDimius

scripts/jobs/validate/partest

@@ -4,5 +4,5 @@ baseDir=${WORKSPACE-`pwd`}
 scriptsDir="$baseDir/scripts"
 . $scriptsDir/common
 
-sbt $sbtArgs update compile "partest-only run"
+sbt $sbtArgs update compile "partest-only run --show-diff --verbose"