MCOP-309 cope with non-responding nodes

The previous implementation of find_applying_nodes would assume that a node had completed if they didn't respond to the puppet.status  action as the code was oriented around processing the results set rather then the expected set of responses.

With this commit we change method to operate in terms of the hosts we expected to hear from, and count the number of times we didn't receive a response to the status action.  If we're unresponded to we increment the :no_response, and on exceeding the threshold we  assume that host is not coming back.