Added missing file.

See GitHub #1, an error in the .gitignore caused this file to be incorrectly ignored. I grabbed the file from the latest release at http://api.metacpan.org/source/THALJEF/Perl-Critic-1.118/inc/Perl/Critic/Module/Build/Standard.pm.
Merge pull request #2 from guillaumeaubert/add_missing_file

Add missing Perl::Critic::Module::Build::Standard