update rubygems and the Dockerfile for rubygems

dockerfiles/rubygems/Dockerfile

@@ -0,0 +1,4 @@
+FROM cybercode/alpine-ruby:2.3
+RUN gem install rubygems-mirror
+ENV BUSYBOX=1
+volume /data

rubygems.sh

@@ -6,6 +6,7 @@ CONF="$HOME/.gem/.mirrorrc"
 mkdir -p "$HOME/.gem"
 
 INIT=${INIT:-"0"}
+BUSYBOX=${BUSYBOX:-"0"}
 
 if [ ! -d "$TUNASYNC_WORKING_DIR" ]; then
 	mkdir -p $TUNASYNC_WORKING_DIR
@@ -14,8 +15,6 @@ fi
 
 echo "Syncing to $TUNASYNC_WORKING_DIR"
 
-if [[ $INIT == "0" ]]; then
-
 cat > $CONF << EOF
 ---
 - from: https://rubygems.org
@@ -26,24 +25,19 @@ if [[ $INIT == "0" ]]; then
 skiperror: true
 EOF
 
-	/usr/bin/timeout -s INT 7200 $GEM mirror  
-	if [[ $? == 124 ]]; then
-		echo 'Sync timeout (/_\\)'
-		exit 1
-	fi
-
+if [[ $INT == "0" ]]; then
+	if [[ $BUSYBOX == "0" ]]; then
+		timeout -t 7200 -s INT $GEM mirror -V
 	else
-
-	cat > $CONF << EOF
----
-- from: https://rubygems.org
-  to: ${TUNASYNC_WORKING_DIR}
-  parallelism: 10
-  retries: 2
-  delete: true
-  skiperror: true
-EOF
-
-	$GEM mirror
-
+		timeout -s INT 7200 $GEM mirror -V
 	fi
+else
+	$GEM mirror -V
+fi
+
+ret=$?
+if [[ $ret == 124 ]]; then
+	echo 'Sync timeout (/_\\)'
+fi
+
+exit $ret