Support Faraday 0.11.x -> 0.13.x

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[Ticket -13]: On upgrade-faraday-13 - Mon 25 Sep 2017 17:40:17 PDT by Geoff Lee <geoff.lee@lendesk.com>

Author: geoff-lee-lendesk

fullcontact.gemspec

@@ -12,7 +12,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'webmock', '~> 1.6'
   s.add_development_dependency 'yard', '~> 0.7'
   s.add_runtime_dependency 'hashie', ['>= 2.0', '< 4.0']
-  s.add_runtime_dependency 'faraday', '~> 0.11.0'
+  s.add_runtime_dependency 'faraday', ['>= 0.11.0', '< 0.14.0']
   s.add_runtime_dependency 'faraday_middleware', '>= 0.10'
 
   s.author = 'FullContact, Inc.'