block device support for launch configurations
block device support for launch configurations

 - mimics block device support from AWS instance
 - splits the acceptance tests out so they all pass, handling a FIXME
   from #1079

charles-at-geospock/terraform-provider-aws,Ninir/terraform-provider-aws,kjmkznr/terraform-provider-aws,ClementCunin/terraform-provider-aws,kjmkznr/terraform-provider-aws,ashinohara/terraform-provider-aws,terraform-providers/terraform-provider-aws,Ninir/terraform-provider-aws,terraform-providers/terraform-provider-aws,ashinohara/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,terraform-providers/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,kjmkznr/terraform-provider-aws,ClementCunin/terraform-provider-aws,nbaztec/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,terraform-providers/terraform-provider-aws,ashinohara/terraform-provider-aws,kjmkznr/terraform-provider-aws,ashinohara/terraform-provider-aws,ClementCunin/terraform-provider-aws,nbaztec/terraform-provider-aws,charles-at-geospock/terraform-provider-aws,nbaztec/terraform-provider-aws,Ninir/terraform-provider-aws,ClementCunin/terraform-provider-aws