Revert "Update client for Faraday 0.9.x changes."

This reverts commit db4b4e8906ed790ce7941fde4940ac81e2c46cf2.

Conflicts:
	lib/attune/default.rb
	lib/attune/version.rb
Downgrade Faraday to 0.8.9.
Reorder encoded params for forward compatibility.

This helps test stubs match requests in both Faraday 0.8.x and 0.9.
Loosen Faraday version requirement to allow 0.9.

Use Faraday 0.8.9 in development to unsure backwards compatibility.
Merge remote-tracking branch 'origin/downgrade-faraday'

Allow backwards compatibility to Faraday 0.8.x.