Make copy_reference_file quieter

Produces way too much output if you have a lot of files in `/usr/share/jenkins/ref`. @reviewbybees
diff --git a/jenkins.sh b/jenkins.sh
index 1bd0f85..acd0d78 100755
--- a/jenkins.sh
+++ b/jenkins.sh
@@ -6,13 +6,10 @@
 # can then change this, upgrade plugins, etc.
 copy_reference_file() {
 	f=${1%/} 
-	echo "$f"
     rel=${f:23}
     dir=$(dirname ${f})
-    echo " $f -> $rel"    
 	if [[ ! -e /var/jenkins_home/${rel} ]] 
 	then
-		echo "copy $rel to JENKINS_HOME"
 		mkdir -p /var/jenkins_home/${dir:23}
 		cp -r /usr/share/jenkins/ref/${rel} /var/jenkins_home/${rel}; 
 	fi;