Only attempt to mount via sftp if we are mounting ftp and port 21

package.json

@@ -91,7 +91,7 @@
         "c9.ide.imgeditor": "#ed89162aa7",
         "c9.ide.immediate": "#6845a93705",
         "c9.ide.installer": "#c36540bd61",
-        "c9.ide.mount": "#d4cfe526e9",
+        "c9.ide.mount": "#f89d3f7570",
         "c9.ide.navigate": "#f358997d93",
         "c9.ide.newresource": "#f1f0624768",
         "c9.ide.openfiles": "#28a4f5af16",