Word Count problem needs more information in its README

[kaushalmodi]

ref

The README for this problem needs to instruct the user to use the critbits library and define the TWordCount custom type using:

import critbits
type TWordCount* = CritBitTree[int]

User can add more imports as they need, but above needs to be the bare-minimum in their submission.

[amscotti]

@kaushalmodi Thanks for your feedback! We can add a hint file to this exercise to give a little bit more details then what's provided by the readme. Also, I'm wondering if this could be rewritten to be a bit simpler but still follow the problem-specifications for this exercise. I'll take a look and see what I can come up with.