Add Enum.reverse/2
Properly .gitignore automatically generated rebar_dep/ebin
Mention File.open/2 modes in File.write/3
Add Enum.intersperse
Merge pull request #1878 from pminten/intersperse

Enum.intersperse, change to join
Ensure test fixtures are kept clean
Update release docs task
Automatically handle File.stream and File.binstream based on modes
Very basic property tester, needs tests

This is a very simple system for testing properties using randomly generated
data like Haskell's QuickCheck does. It doesn't yet provide any helpers to make
data generation easier.
proptest generators now throw on no value

This is easier to work with than the list return system.