Added setMinCount to Word2Vec.scala

Wanted to customize the private minCount variable in the Word2Vec class. Added
a method to do so.

Author: ganonp <ganonp@gmail.com>

Closes #3693 from ganonp/my-custom-spark and squashes the following commits:

ad534f2 [ganonp] made norm method public
5110a6f [ganonp] Reorganized
854958b [ganonp] Fixed Indentation for setMinCount
12ed8f9 [ganonp] Update Word2Vec.scala
76bdf5a [ganonp] Update Word2Vec.scala
ffb88bb [ganonp] Update Word2Vec.scala
5eb9100 [ganonp] Added setMinCount to Word2Vec.scala