Fix logic errors in validate cluster and make it work for vagrant again

There were a couple of issues this resolved:

function get-password 
was not abstracted into kube-util as a common top level function, so it had no implementation in the vagrant based functions.

the check on grep for count did not work when count == 0 because the script would exit out because grep returns an exit status of 1 when no match is found.  this caused the set -e to trigger, and script never proceeded.  modified to always || the output of grep with non-error result so script would proceed.