Update sinatra to v1.4.4

Author: Chris Hunt

github-auth.gemspec

@@ -25,7 +25,7 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'pry',            '~> 0.9.12.4'
   spec.add_development_dependency 'rake',           '~> 10.1.1'
   spec.add_development_dependency 'rspec',          '~> 2.14.1'
-  spec.add_development_dependency 'sinatra',        '~> 1.4.3'
+  spec.add_development_dependency 'sinatra',        '~> 1.4.4'
   spec.add_development_dependency 'thin',           '~> 1.5.1'
 
   spec.add_runtime_dependency 'httparty', '~> 0.12.0'