add CONTRIBUTING.md
add support for ffmpeg/ffprobe version 2.2.2
enable rspec warnings
fix shadowing path in ffprober.rb:15
relax rspec dependency and add a sample spec_helper
update Changes.md
Merge pull request #38 from mbkulik/ffmpeg-2.2.2-support

add support for ffmpeg/ffprobe version 2.2.2
Merge pull request #39 from beanieboi/feature/upgrade-rspec

Feature/upgrade rspec
allow all object attributes, smaller cleanup
fix variable shadowing
set max version to 2.2.2
Merge pull request #40 from beanieboi/feature/refactor

allow all object attributes, smaller cleanup
Merge remote-tracking branch 'origin/master' into feature/chapters

Conflicts:
	Changes.md
	lib/ffprober.rb
	lib/ffprober/format.rb
	lib/ffprober/parser.rb
	lib/ffprober/stream.rb