Rakefile: Change metadata task to metadata_lint
Rakefile: Change metadata task to metadata_lint

Fixes https://github.com/dfarrell07/puppet-opendaylight/issues/115

Signed-off-by: srisankethu <82a3e4e4a1a98803797f621c835ed7bd2bc21754@research.iiit.ac.in>

umeshksingla/puppet-opendaylight,srisankethu/puppet-opendaylight,srisankethu/puppet-opendaylight,umeshksingla/puppet-opendaylight