(maint) Pin rake to the last 1.8 compatible version

Author: Kylo Ginsberg

Gemfile

@@ -7,7 +7,7 @@ group :development do
 end
 
 group :development, :test do
-  gem 'rake'
+  gem 'rake', "~> 10.1.0"
   gem 'rspec', "~> 2.11.0", :require => false
   gem 'mocha', "~> 0.10.5", :require => false
   gem 'json', "~> 1.7", :require => false, :platforms => :ruby