Add Include option

[pjanotti]

Per discussion #141 (comment)

Adding an Include option is a no brainer and that change is quite simple. I'll go ahead and get that in, but one will have to take precedence. Considering the most likely scenario is that the developer will want to exclude, Include will be ignored if Exclude is also specified.

[pjanotti]

I will give a try at this later today (unless someone is already working on it).