Merge pull request #316 from hardillb/install-tgz-package

Add description of TGZ install options

Author: Steve-Mcl

docs/api/admin/methods/post/nodes/index.md

@@ -19,12 +19,13 @@ Requires permission: <code>nodes.write</code>
 Header          | Value
 ----------------|-------
 `Authorization` | `Bearer [token]` - if authentication is enabled
-`Content-type`  | `application/json`
+`Content-type`  | `application/json` - if installing from a npm repository
+`Content-type`  | `multipart/form-data` - if installing a tgz package
 
 
 ### Arguments
 
-The request body must be a JSON string with the following fields:
+When installing a package from a npm repository the request body must be a JSON string with the following fields:
 
 Field    | Description
 ---------|-----------------------
@@ -36,6 +37,14 @@ Field    | Description
 }
 {% endhighlight %}
 
+If installing a tgz package the request body must be a `multipart/form-data` 
+
+The following `curl` example will install `node-red-contrib-foo`.
+
+{% highlight shell %}
+curl -X POST http://localhost:1880/nodes -H "Content-Type: multipart/form-data" -F "tarball=@node-red-contrib-foo-1.0.3.tgz;type=application/x-compressed-tar;filename=node-red-contrib-foo-1.0.3.tgz"
+{% endhightlight  %}
+
 ### Response
 
 Status Code | Reason         | Response