changes to satisfy item #68 by using update-rc.d and service commands vs. the ansible service module. See ansible/ansible#8987 for details.
Default to flat image type per #67
zero out unused bit of filesystem if buri_disk_zerofill is set to always, or there is an instance image being made. skip if set to never. default is "normal" for #63
add buri frontend params for disk zeroing control
let the EBS volume type be specified
fixes for gp2 support, took out io1 for now... aws cli has a real problem with keeping the same ordinal positions for its output in text format... adjusted for both the standard and gp2 cases
rework the volume create/attach, as we tickled an Ansible quirk around conditional blocks and registers being wiped by the skipped block. new volumes and those resnapped have their own entry points, and the common elements are pulled out to a new file.
add files that should have been part of prior commit.
be even MORE patient with EC2 re: waiting for snapshots to complete. (up to 5 minutes vs. 3)