add atlas post-processor docs

website/source/docs/post-processors/atlas.html.markdown

+---
+layout: "docs"
+page_title: "Atlas Post-Processor"
+description: |-
+  The Atlas post-processor for Packer receives an artifact from a Packer build and uploads it to Atlas. Atlas hosts and serves artifacts, allowing you to version and distribute them in a simple way.
+---
+
+# Atlas Post-Processor
+
+Type: `atlas`
+
+The Atlas post-processor for Packer receives an artifact from a Packer build and uploads it to Atlas. [Atlas](https://atlas.hashicorp.com) hosts and serves artifacts, allowing you to version and distribute them in a simple way. 
+
+## Workflow
+
+To take full advantage of Packer and Atlas, it's important to understand the 
+workflow for creating artifacts with Packer and storing them in Atlas using this post-processor. The goal of the Atlas post-processor is to streamline the distribution of public or private artifacts by hosting them in a central location in Atlas.
+
+Here is an example workflow:
+
+1. Packer builds an AMI with the [Amazon AMI builder](http://www.packer.io/docs/builders/amazon.html)
+2. The `atlas` post-processor takes the resulting AMI and uploads it to Atlas. The `atlas` post-processor is configured with the name of the AMI, for example `hashicorp/foobar`, to create the artifact in Atlas or update the version if the artifact already exists
+4. The version is released and available to be used in deployments with a tool like [Terraform](https://terraform.io)
+
+
+## Configuration
+
+The configuration allows you to specify and access the artifact in Atlas. 
+
+### Required:
+
+* `token` (string) - Your access token for the Atlas API.
+  This can be generated on your [tokens page](https://atlas.hashicorp.com/settings/tokens). Alternatively you can export your Atlas token as an environmental variable and remove it from the configuration. 
+
+* `artifact` (string) - The shorthand tag for your artifact that maps to
+  Atlas, i.e `hashicorp/foobar` for `atlas.hashicorp.com/hashicorp/foobar`. You must 
+  have access to the organization, hashicorp in this example, in order to add an artifact to 
+  the organization in Atlas. 
+
+* `artifact_type` (string) - For uploading AMIs to Atlas, `artifact_type` will always be `aws.ami`.
+  This field must be defined because Atlas can host other artifact types, such as Vagrant boxes.
+
+### Optional:
+
+* `atlas_url` (string) - Override the base URL for Atlas. This
+is useful if you're using Atlas Enterprise in your own network. Defaults
+to `https://atlas.hashicorp.com/api/v1`.
+
+* `metadata` (map) - Send metadata about the artifact.
+
+### Example Configuration
+
+```javascript
+{
+    "variables": {
+        "aws_access_key": "ACCESS_KEY_HERE",
+        "aws_secret_key": "SECRET_KEY_HERE",
+        "atlas_token": "ATLAS_TOKEN_HERE"
+    },
+    "builders": [{
+        "type": "amazon-ebs",
+        "access_key": "{{user `aws_access_key`}}",
+        "secret_key": "{{user `aws_secret_key`}}",
+        "region": "us-east-1",
+        "source_ami": "ami-de0d9eb7",
+        "instance_type": "t1.micro",
+        "ssh_username": "ubuntu",
+        "ami_name": "atlas-example {{timestamp}}"
+    }],
+    "provisioners": [
+    {
+        "type": "shell",
+        "inline": [
+            "sleep 30",
+            "sudo apt-get update",
+            "sudo apt-get install apache2 -y"
+        ]
+    }],
+    "post-processors": [
+      {
+        "type": "atlas",
+        "token": "{{user `atlas_token`}}",
+        "artifact": "hashicorp/foobar",
+        "artifact_type": "aws.ami",
+        "metadata": {
+          "created_at": "{{timestamp}}"
+        }
+      }
+    ]
+}
+```

website/source/layouts/docs.erb

@@ -60,6 +60,7 @@
 
 		<ul>
 			<li><h4>Post-Processors</h4></li>
+			<li><a href="/docs/post-processors/atlas.html">Atlas</a></li>
 			<li><a href="/docs/post-processors/compress.html">compress</a></li>
 			<li><a href="/docs/post-processors/docker-import.html">docker-import</a></li>
 			<li><a href="/docs/post-processors/docker-push.html">docker-push</a></li>