fix(serializer): ensure RegExp options are alphabetically sorted

Author: mbroadst

Diff for: lib/bson/parser/serializer.js

@@ -201,8 +201,8 @@ var serializeRegExp = function(buffer, key, value, index, isArray) {
   // Write zero
   buffer[index++] = 0x00;
   // Write the parameters
-  if (value.global) buffer[index++] = 0x73; // s
   if (value.ignoreCase) buffer[index++] = 0x69; // i
+  if (value.global) buffer[index++] = 0x73; // s
   if (value.multiline) buffer[index++] = 0x6d; // m
 
   // Add ending zero