Added link to the upgrading page in the docs.

Author: jonathanslenders

docs/index.rst

@@ -3,12 +3,10 @@ Python Prompt Toolkit 2.0
 
 .. warning::
 
- Please notice that this is the documentation for the 2.0 branch of
- prompt_toolkit. It is incompatible with the 1.0 branch, but much better in
- many regards. On Pypi you'll still find the 1.0 branch, but a release
- should follow soon. In the meantime, don't hesitate to test this branch and
- report any bugs.
-
+ Notice that this is the prompt_toolkit 2.0 documentation. It is
+ incompatible with the 1.0 branch, but much better in many regards. Please
+ read :ref:`Upgrading to prompt_toolkit 2.0 <upgrading_2_0>` for more
+ information.
 
 `prompt_toolkit` is a library for building powerful interactive command line
 and terminal applications in Python.

docs/pages/upgrading.rst

@@ -1,9 +1,11 @@
+.. _upgrading_2_0:
+
 Upgrading to prompt_toolkit 2.0
 ===============================
 
-Prompt_toolkit 2.0 is not compatible with 1.0, however you want to upgrade your
-applications. This page explains why we have these differences and how to
-upgrade.
+Prompt_toolkit 2.0 is not compatible with 1.0, however you probably want to
+upgrade your applications. This page explains why we have these differences and
+how to upgrade.
 
 If you experience some difficulties or you feel that some information is
 missing from this page, don't hesitate to open a GitHub issue for help.