Trying to run grunt build on a Yeoman scaffolded app with grunt-angular-templates as one of the tasks, generates the following errors:

>> Tasks directory "grunt-angular-templates" not found.

Also gives the following error:

Running "ngtemplates:TestApp" (ngtemplates) task
Warning: Object.keys called on non-object Use --force to continue.

Isolated run command: grunt ngtemplates:TestApp

Link to TestApp below:
Github repo

I'm not sure what is causing these errors.