Update documentation with new selector keys.

src/blenderbim/docs/devs/writing_docs.rst

@@ -13,6 +13,11 @@ All documentation is written in ReStructured Text and is available in the
 `BlenderBIM Add-on docs directory
 <https://github.com/IfcOpenShell/IfcOpenShell/tree/v0.7.0/src/blenderbim/docs>`_.
 
+You can link to `external websites <https://ifcopenshell.org>`_. You can also
+link to sections on the same page, like `Writing technical documentation`_.
+
+:doc:`Code examples<code_examples>`
+
 The following colours and annotation styles should be used for annotating
 images. All stroke widths are 3px with a corner radius of 3px.  Horizontal
 underlines are 5px with a corner radius of 2px. The dark green is ``39b54a`` and
@@ -43,6 +48,16 @@ download.
 
     `Visit critical link <https://blenderbim.org>`__
 
+You can use bulleted lists:
+
+- Like.
+- This.
+
+Or ordered lists:
+
+1. Like.
+2. This.
+
 .. note::
 
    Instead of writing "Note that XYZ ..." you should use notes sparingly to