compile.sh: report downloading gradle

Otherwise upon starting the script while waiting for it to download gradle, it appers to hang.

compile.sh

@@ -75,6 +75,7 @@ checkfail()
 ##########
 
 if [ ! -d "gradle/wrapper" ]; then
+    echo "Downloading gradle"
     GRADLE_VERSION=2.2.1
     GRADLE_URL=http://services.gradle.org/distributions/gradle-${GRADLE_VERSION}-all.zip
     wget ${GRADLE_URL} 2>/dev/null || curl -O ${GRADLE_URL}