Upgraded faraday and fixed minor test syntax change

@sbfaulkner - This PR upgrades Faraday to 0.9.0. We were getting some errors with applications that used the gem inside the Retry class in Faraday. When I was investigating the source of the retry to track it down, 0.9.x completely rewrites that class...so I thought that I'd just update the gem inside MosaicFacebook.

I had to update the VCR files, because Faraday 0.8.x sends a empty parameter as
    
     http://example.com?myparam

whereas 0.9.0 sends it as

    http://example.com?myparam=

They should be functionally identical, but it caused all our cassettes to fail the match.

Because I bumped the version of a pretty core gem, I incremented the minor version level instead of the patch.