Make Ansible extra_vars a hash instead of a string
Merge pull request #1550 from commandtab/ansible_extra_vars_hash

Make Ansible provisioner extra_vars a hash
Validate that extra_vars is a hash
Merge pull request #1551 from commandtab/validate_ansible_extra_vars

Validate that Ansible extra_vars is a hash
s/not/!/ in ansible provisioner config