docstrings: fix "Sphinx param with type" pattern (#807)

* docstrings: fix "Sphinx param with type" pattern

Previously, the pattern only matched if the parameter description
followed on the same line, like so:

    :param type foo: A param named foo.

However, it's also valid for the parameter description to be wrapped
onto the next line, like so:

    :param type foo:
        A param named foo.

This change updates the pattern to match the second example as well, and
adds a test to verify this behaviour.

Fixes #806.

* Add Simon Ruggier to the AUTHORS file

AUTHORS.txt

@@ -42,6 +42,7 @@ Cristi Burcă (@scribu)
 bstaint (@bstaint)
 Mathias Rav (@Mortal) <rav@cs.au.dk>
 Daniel Fiterman (@dfit99) <fitermandaniel2@gmail.com>
+Simon Ruggier (@sruggier)
 
 
 Note: (@user) means a github user name.