(maint) Update to modern Rspec-puppet setup

To get tests to compile on latest Puppet 5:

- dependency on librarian-puppet removed in favour of using
  puppetlabs_spec_helper / .fixtures.yml to install deps

- let blocks to declare the ant class added in various places as Puppet
  4/5 seems to be more picky about this

- unneeded Gems removed from Gemfile, and bundle updated.

- deprecation warnings silenced by removing custom logging functionality
  from spec_helper.rb.

Author: alex-harvey-z3q

.fixtures.yml

@@ -1,3 +1,6 @@
 fixtures:
+  forge_modules:
+    stdlib: puppetlabs/stdlib
+    wget: maestrodev/wget
   symlinks:
     ant: "#{source_dir}"

Gemfile

@@ -1,17 +1,7 @@
-# This file is managed centrally by modulesync
-#   https://github.com/maestrodev/puppet-modulesync
-
 source 'https://rubygems.org'
 
 gem 'puppet', ENV['PUPPET_VERSION'] || '>= 2.7', :require => false
-
-gem 'rake', :require => false
-gem 'rspec-puppet', '>= 1.0.0', :require => false
-gem 'puppetlabs_spec_helper', '>= 0.8.0', :require => false
-gem 'puppet-lint', '>= 1.1.0', :require => false
-gem 'simplecov', :require => false
-gem 'puppet-blacksmith', '>= 3.0.0', :require => false
-gem 'librarian-puppet', '>= 2.0.0', :require => false
-gem 'beaker-rspec', '>= 3.0.0', :require => false
+gem 'puppetlabs_spec_helper', :require => false
+gem 'beaker-rspec', :require => false
 
 # vim:ft=ruby