(PUP-3695) yum provider handling for --disableexcludes in :install_options

Add special handling --disableexcludes=<foo> options when passed in via
install_options, similar to the existing support for --enablerepo and
--disablerepo.
Merge pull request #3336 from jhoblitt/feature/master/pup-3695-yum-provider-disableexcludes

(PUP-3695) yum provider handling for --disableexcludes in :install_options