Add distinct method to RichPipe and TypedPipe, as well as corresponding tests.
Change implementation of distinct to a more type-clear way.Add docstring
Merge pull request #413 from reconditesea/klin_add_distinct

Add distinct method to RichPipe and TypedPipe
Cleanr and update RichPipe docstrings.
 Two minor changes on docstrings.
Merge pull request #417 from reconditesea/klin_richPipiDoc

Clean and update RichPipe docstrings.
Add drop/dropWhile/take/takeWhile to KeyedList
Merge pull request #420 from reconditesea/klin_add_I414

Add drop/dropWhile/take/takeWhile to KeyedList
Use Long instead of Int for the counter in histogram
Add idea-gen and scalatest
Code formatting