Singularize bug for words such as rookies and beanies

[intentionally-left-nil]

All of the words in singular_ie inside of inflect.py aren't being singularized properly.

The code in question is

    for x in singular_ie:
        if w.endswith(x+"s"):
            return w

Instead of returning the singular form (x), it returns the plural one (w).

I will make a PR