(maint) add VCR to the bundle and configure it for rspec

VCR allows more straight-forward stubbing in HTTP tests.
The suggestion was made by Adrien Thebo, and the configuration
was adapted from the one in r10k.

Author: ffrank

Gemfile

@@ -49,6 +49,9 @@ group(:development, :test) do
   gem "rubocop", "~> 0.26.1", :platforms => [:ruby]
 
   gem 'rdoc', "~> 4.1", :platforms => [:ruby]
+
+  gem 'webmock'
+  gem 'vcr', '~> 2.9'
 end
 
 group(:development) do

spec/spec_helper.rb

@@ -43,6 +43,13 @@ module PuppetSpec
   require behaviour.relative_path_from(Pathname.new(dir))
 end
 
+require 'vcr'
+VCR.configure do |vcr|
+  vcr.cassette_library_dir = File.expand_path('vcr/cassettes', PuppetSpec::FIXTURE_DIR)
+  vcr.hook_into :webmock
+  vcr.configure_rspec_metadata!
+end
+
 RSpec.configure do |config|
   include PuppetSpec::Fixtures