'this.templateDir' needs to be changed to 'template'... Otherwise it will be undefined:

```
[ERROR] Failed to run command "create"
[ERROR] TypeError: Arguments to path.join must be strings
    at path.js:360:15
    at Array.filter (native)
    at exports.join (path.js:358:36)
    at copyFiles (/Users/ayeung/titanium/titanium_mobile/dist/mobilesdk/osx/3.3.0/cli/lib/app-creator.js:87:26)
    at AppCreator.run (/Users/ayeung/titanium/titanium_mobile/dist/mobilesdk/osx/3.3.0/cli/lib/app-creator.js:59:14)
    at AppCreator.<anonymous> (/Users/ayeung/titanium/titanium_mobile/dist/mobilesdk/osx/3.3.0/cli/commands/create.js:356:11)
    at CLI._fireHookCallback (/usr/local/lib/node_modules/titanium/lib/hook.js:245:12)
    at /usr/local/lib/node_modules/titanium/lib/hook.js:224:10
    at /usr/local/lib/node_modules/titanium/node_modules/async/lib/async.js:232:13
    at async.eachSeries (/usr/local/lib/node_modules/titanium/node_modules/async/lib/async.js:130:20)

```