(GH-646) Use Package[sensu], not Package[Sensu] on Windows
(GH-646) Use Package[sensu], not Package[Sensu] on Windows

Partially resolves #646

Still running into this error:

    Error: Parameter ensure failed on Package[sensu]: Provider windows
    must have features 'upgradeable' to set 'ensure' to 'latest' at
    sensu/manifests/package.pp:64

jeffmccune/sensu-puppet,madelaney/sensu-puppet,bodgit/sensu-puppet,jeffmccune/sensu-puppet,dzeleski/sensu-puppet,bovy89/sensu-puppet,sensu/sensu-puppet,bovy89/sensu-puppet,bovy89/sensu-puppet,bodgit/sensu-puppet,sensu/sensu-puppet,dzeleski/sensu-puppet,dzeleski/sensu-puppet,jeffmccune/sensu-puppet,madelaney/sensu-puppet,bodgit/sensu-puppet,sensu/sensu-puppet,madelaney/sensu-puppet