[Breaking Change] Collection#truncate! is now Collection#truncate
Merge pull request #114 from triAGENS/truncate-no-bang

[Breaking Change] Collection#truncate! is now Collection#truncate
Faraday and Faraday Middleware Version Bump

* Faraday is now on version 0.9.0
* Faraday Middleware is now on version 0.9.1
Update Development Dependencies: Rake, Inch, Mutant, Guard