title: Add uppercase: true to mongoose embedded document
body: <p>If I have two schemas, one which will be embedded in the other:</p>
  
  <pre><code>var mongoose = require("mongoose");
  var Schema = mongoose.Schema;
  
  // Will embed this in the personSchema below
  var addressSchema = new Schema({
      street: String,
      city: String,
      state: {
          type: String,
          uppercase: true
      },
      zip: Number
  });
  
  var personSchema = new Schema({
      firstName: {
          type: String,
          required: true
      },
      lastName: {
          type: String,
          required: true
      },
      emailAddress: {
          type: String,
          lowercase: true
      },
      phoneNumber: Number,
      address: addressSchema
  });
  
  module.exports = mongoose.model("Person", personSchema);
  </code></pre>
  
  <p>I can't seem to get the <code>uppercase: true</code> to work for embedded documents - no error is thrown, but it simply doesn't uppercase the state property. Or any kind of option like that.</p>
  
  <p>I've been searching the Mongoose docs, but maybe I'm just not finding where it mentions that settings these kinds of additional options on subDocuments won't work.</p>