Fixes config error with string value.

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/commands/config.js

@@ -80,7 +80,11 @@ cmd.handler = function(argv) {
   }
 
   // set
-  nconf.set(argv.key, JSON.parse(argv.value));
+  try {
+    nconf.set(argv.key, JSON.parse(argv.value));
+  } catch (e) {
+    nconf.set(argv.key, JSON.parse('"' + argv.value + '"'));
+  }
   return saveConfig();
 };