make docker-push work with docker-tag artifacts

website: Add all boot commands from source to docs.

website: Minor edits

website: Update chef-solo.html.markdown

website: Update amazon.html.markdown

post-processor/parallels: Removed unnecessary filling the Vagranfile

website: ec2:ModifyImageAttribute already included in the sample policy

providers/aws: Ignore transient network errors when fetching AWS state.

website: Update example to match parameter.

provisioner/ansible: Colorize Ansible output, and don't buffer output.

provisioner/shell: single quote env var values.

Setting environment variables for the ansible-playbook invocation.

ANSIBLE_FORCE_COLOR will ensure output is colorized.  PYTHONUNBUFFERED will stream output as Ansible runs, vs getting a big dump of output at the end.

The example showed "path" instead of "output".

Given that state fetching is an idempotent operation, a transient
network error should not cause the entire build to fail. Instead,
retry when such errors are encountered.

fix a minor typo in platforms.html

fix: Respect metadata supplied for GCE builders.

Fixed dead links in doc section environment-variables.

Use middleman-hashicorp

Previously, any per instance metadata supplied via the GCE builder
was ignored.

Test plan:

- make test
- Manual testing via:
-- Created a packer config that contained a GCE builder with custom
   metadata set.
-- Ran `packer build`.
-- Verified the instance had the correct metadata in the GCE console.

ec2:ModifyImageAttribute is already included in the sample policy JSON (line 67 in the source file), so the comment about optionally adding it only adds confusion.

builder/parallels: Create VM without hdd and then add it later

builder/parallels: Rely on Cleanup functions to detach devices

This is needed to make 'cdrom0' device unavailable during the ISO installation process.
It is required for some guest OS types, such as FreeBSD and OmniOS.