Rename exec, move command to command parameter
Rename exec, move command to command parameter

Easier to figure out what the exec is doing, and makes the specs a little nicer.
mhaskel/puppetlabs-git,johnduarte/puppetlabs-git,coffeecoco/puppet-git,puppetlabs/puppetlabs-git,coffeecoco/puppet-git,michaeldfallen/puppetlabs-git,johnduarte/puppetlabs-git,mbrodala/puppetlabs-git,puppetlabs/puppetlabs-git,pagemachine/puppetlabs-git,michaeldfallen/puppetlabs-git,mhaskel/puppetlabs-git,redhat-cip/puppetlabs-git,pagemachine/puppetlabs-git,patrickkelso/puppetlabs-git,redhat-cip/puppetlabs-git,patrickkelso/puppetlabs-git,gwdg/puppetlabs-git,gwdg/puppetlabs-git,mbrodala/puppetlabs-git