website: fix docs installation page

website/source/docs/installation.html.markdown

@@ -1,7 +1,52 @@
 ---
 layout: "docs"
+page_title: "Install Packer"
 ---
 
-# Installing Packer
+# Install Packer
 
-Coming soon.
+Packer must first be installed on the machine you want to run it on.
+To make installation easy, Packer is distributed as a [binary package](#)
+for all supported platforms and architectures. This page will not cover how
+to compile Packer from source, as that is covered in the
+[README](https://github.com/mitchellh/packer/blob/master/README.md) and is only
+recommended for advanced users.
+
+## Installing Packer
+
+To install packer, first find the [appropriate package](#)
+for your system and download it. Packer is packaged as a "zip" file.
+
+Next, unzip the downloaded package into a directory where Packer will be
+installed. On Unix systems, `~/packer` or `/usr/local/packer` is generally good,
+depending on whether you want to restrict the install to just your user
+or install it system-wide. On Windows systems, you can put it whereever you'd
+like.
+
+After unzipping the package, the directory should contain a set of binary
+programs, such as `packer`, `packer-build-amazon-ebs`, etc. The final step
+to installation is to make sure the directory you installed Packer to
+is on the PATH. See [this page](http://stackoverflow.com/questions/14637979/how-to-permanently-set-path-on-linux)
+for instructions on setting the PATH on Linux and Mac.
+[This page](http://stackoverflow.com/questions/1618280/where-can-i-set-path-to-make-exe-on-windows)
+contains instructions for setting the PATH on Windows.
+
+## Verifying the Installation
+
+After installing Packer, verify the installation worked by opening
+a new command prompt or console, and checking that `packer` is available:
+
+```
+$ packer
+usage: packer [--version] [--help] <command> [<args>]
+
+Available commands are:
+    build        build image(s) from template
+    validate     check that a template is valid
+```
+
+If you get an error that `packer` could not be found, then your PATH
+environmental variable was not setup properly. Please go back and ensure
+that yoru PATH variable contains the directory which has Packer installed.
+
+Otherwise, Packer is installed and you're ready to go!