docs: Improve readme

Use text from www.mopidy.com. Change "Download development snapshot" link,
which confused some new users.

README.rst

@@ -2,24 +2,57 @@
 Mopidy
 ******
 
-Mopidy is a music server which can play music both from multiple sources, like
-your local hard drive, radio streams, and from Spotify and SoundCloud. Searches
-combines results from all music sources, and you can mix tracks from all
-sources in your play queue. Your playlists from Spotify or SoundCloud are also
-available for use.
+Mopidy is an extensible music server written in Python.
 
-To control your Mopidy music server, you can use one of Mopidy's web clients,
-the Ubuntu Sound Menu, any device on the same network which can control UPnP
-MediaRenderers, or any MPD client. MPD clients are available for many
-platforms, including Windows, OS X, Linux, Android and iOS.
+Mopidy plays music from local disk, Spotify, SoundCloud, Google Play Music, and
+more. You edit the playlist from any phone, tablet, or computer using a range
+of MPD and web clients.
 
-To get started with Mopidy, check out `the docs <http://docs.mopidy.com/>`_.
+**Stream music from the cloud**
+
+Vanilla Mopidy only plays music from your local disk and radio streams.
+Through extensions, Mopidy can play music from cloud services like Spotify,
+SoundCloud, and Google Play Music. With Mopidy's extension support, backends
+for new music sources can be easily added.
+
+**Mopidy is just a server**
+
+Mopidy is a Python application that runs in a terminal or in the background on
+Linux computers or Macs that have network connectivity and audio output. Out of
+the box, Mopidy is an MPD and HTTP server. Additional frontends for controlling
+Mopidy can be installed from extensions.
+
+**Everybody use their favorite client**
+
+You and the people around you can all connect their favorite MPD or web client
+to the Mopidy server to search for music and manage the playlist together. With
+a browser or MPD client, which is available for all popular operating systems,
+you can control the music from any phone, tablet, or computer.
+
+**Mopidy on Raspberry Pi**
+
+The Raspberry Pi is a popular device to run Mopidy on, either using Raspbian or
+Arch Linux. It is quite slow, but it is very affordable. In fact, the
+Kickstarter funded Gramofon: Modern Cloud Jukebox project used Mopidy on a
+Raspberry Pi to prototype the Gramofon device. Mopidy is also a major building
+block in the Pi Musicbox integrated audio jukebox system for Raspberry Pi.
+
+**Mopidy is hackable**
+
+Mopidy's extension support and Python, JSON-RPC, and JavaScript APIs makes
+Mopidy perfect for building your own hacks. In one project, a Raspberry Pi was
+embedded in an old cassette player. The buttons and volume control are wired up
+with GPIO on the Raspberry Pi, and is used to control playback through a custom
+Mopidy extension. The cassettes have NFC tags used to select playlists from
+Spotify.
+
+To get started with Mopidy, check out
+`the installation docs <http://docs.mopidy.com/en/latest/installation/>`_.
 
 - `Documentation <http://docs.mopidy.com/>`_
 - `Source code <https://github.com/mopidy/mopidy>`_
 - `Issue tracker <https://github.com/mopidy/mopidy/issues>`_
-- `CI server <https://travis-ci.org/mopidy/mopidy>`_
-- `Download development snapshot <https://github.com/mopidy/mopidy/archive/develop.tar.gz#egg=mopidy-dev>`_
+- `Development branch tarball <https://github.com/mopidy/mopidy/archive/develop.tar.gz#egg=mopidy-dev>`_
 
 - IRC: ``#mopidy`` at `irc.freenode.net <http://freenode.net/>`_
 - Mailing list: `mopidy@googlegroups.com <https://groups.google.com/forum/?fromgroups=#!forum/mopidy>`_