Add parameter parsing in FPGrowth example app in Scala and Java
And a sample data file is added in data/mllib folder
Author: Jacky Li <jacky.likun@huawei.com>
Closes#4714 from jackylk/parameter and squashes the following commits:
8c478b3 [Jacky Li] fix according to comments
3bb74f6 [Jacky Li] make FPGrowth exampl app take parameters
f0e4d10 [Jacky Li] make FPGrowth exampl app take parameters