add lock to removeWallet

lib/server.js

@@ -468,10 +468,18 @@ CopayServer.prototype.getTx = function(opts, cb) {
 
 
 /**
- * Remove wallet
+ * removeWallet
+ *
+ * @param opts
+ * @param cb
+ * @return {undefined}
  */
 CopayServer.prototype.removeWallet = function(opts, cb) {
-  this.storage.removeWallet(this.walletId, cb);
+  var self = this;
+
+  Utils.runLocked(self.walletId, cb, function(cb) {
+    self.storage.removeWallet(self.walletId, cb);
+  });
 };