`singularize()` incorrectly singularizes "alumnus"

[ultimatedelman]

Ember.Inflector.inflector.singularize('alumnus'); // "alumnu"

[stefanpenner]

from the readme:

Ember Inflector aims to be compatible with ActiveSupport::Inflector from Ruby on Rails

Rails has decided to freeze its default inflection rules, and to match parity so have we.

One can still add additional app specific inflections, see: https://github.com/stefanpenner/ember-inflector#usage for further examples of how one does this.