Merge pull request #100 from signalapp/jack/log-java-exceptions

Have Maven log stack traces of tests that fail with exceptions

java/java/build.gradle

@@ -62,6 +62,10 @@ test {
     testLogging {
         events 'passed'
         showStandardStreams = true
+        showExceptions true
+        exceptionFormat 'full'
+        showCauses true
+        showStackTraces true
     }
 
     include 'org/whispersystems/**'