Editing Sam's downloads page

src/site/_includes/downloads/_linux_section.html

+First install Dart, and then choose your editor.
+(Don't care which editor you use?
+Skip to [Step 2](#step-2-pick-an-editor-linux) and choose **Dart Editor**,
+which includes Dart.)
+
+## Step 1: Install Dart
+
+Choose either:
+
+* [Server-side development for Debian/Ubuntu](#debian)
+* [Other Linux development](#other)
+
+If you want to build Dart from scratch, see
+[Compiling from source](#compiling-from-source).
+
+### Installing for server-side development on Debian/Ubuntu {#debian}
+
+Get a 64-bit version of the Dart SDK that's easy to update:
+
+{% prettify sh %}
+# Enable HTTPS for apt.
+$ sudo apt-get update
+$ sudo apt-get install apt-transport-https
+# Get the Google Linux package signing key.
+$ sudo sh -c 'curl https://dl-ssl.google.com/linux/linux_signing_key.pub | apt-key add -'
+# Set up the location of the stable repository.
+$ sudo sh -c 'curl https://storage.googleapis.com/download.dartlang.org/linux/debian/dart_stable.list > /etc/apt/sources.list.d/dart_stable.list'
+$ sudo apt-get update
+$ sudo apt-get install dart
+{% endprettify %}
+
+For more information about other options for Debian, visit the
+[Dart Debian downloads page](/tools/debian.html).
+
+
+### Installing on other Linux distros {#other}
+
+You can manually download and extract the Dart SDK from a zip file:
+
+<p class="os-choices">
+{% include downloads/_sdk.html buttonclass="btn btn-primary btn-lg" %}
+</p>
+
+If you're creating Dart web apps, also download Dartium:
+
+<p>
+{% include downloads/_dartium.html buttonclass="btn btn-primary btn-lg download-btn" %}
+</p>
+
+The Dartium binary expires after 12 weeks.  When that happens, you need to
+download a new copy to continue using Dartium.
+
+### Compiling from source
+
+You can [build the SDK](https://code.google.com/p/dart/wiki/Building) yourself.
+If your system uses an older version of Ubuntu,
+you might need to update to GCC 4.6 or later.
+See the [Tools FAQ](/tools/faq.html) for more information.