doc/index: add basic welcome page

doc/api/index.rst

@@ -1,7 +1,49 @@
-Pybricks
+Welcome to Pybricks!
 ==================================================================
 
-Intro
+This documentation has everything you need to install Pybricks and
+run your first scripts.
+
+
+**Step 1: Install Pybricks**
+
+To get started, go to the :doc:`EV3 Quick Start <start_ev3>`
+or the :doc:`Powered Up Quick Start <start_ev3>` or pick your hub
+below.
+
+.. list-table::
+
+   * - **EV3 Brick**
+     - **Move Hub**
+     - **City Hub**
+     - **Control+ Hub**
+
+   * - .. image:: images/ev3brick.png
+         :target: start_ev3.html
+
+     - .. figure:: images/movehub.png
+         :target: start_pup.html
+
+     - .. figure:: images/cityhub.png
+         :target: start_pup.html
+
+     - .. figure:: images/cplushub.png
+          :target: start_pup.html
+
+
+**Step 2: Start coding!**
+
+After you've followed the installation steps for your hub,
+check out the Pybricks modules in the left hand menu to see what
+you can do.
+
+**Step 3: Share what you made (or ask for help!)**
+
+Got questions or issues? Please share your
+findings on our `support page`_ so we can make Pybricks better. *Thank you!*
+
+
+.. _support page: https://github.com/pybricks/support/issues/
 
 .. toctree::
     :maxdepth: 1
@@ -16,6 +58,7 @@ Intro
     Home Page <https://pybricks.com>
     Downloads <https://pybricks.com/downloads/>
     Example Projects <https://github.com/pybricks/pybricks-projects>
+    Support <https://github.com/pybricks/support/issues/>
 
 .. toctree::
    :maxdepth: 1