Sphinxify the developer policy document.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158814 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/userguides.rst b/docs/userguides.rst
index 0d1f3fb..57058ee 100644
--- a/docs/userguides.rst
+++ b/docs/userguides.rst
@@ -7,6 +7,7 @@
    :hidden:
 
    CommandGuide/index
+   DeveloperPolicy
    FAQ
    Lexicon
 
@@ -32,7 +33,7 @@
    A walk through the process of using LLVM for a custom language, and the
    facilities LLVM offers in tutorial form.
 
-* `Developer Policy <DeveloperPolicy.html>`_
+* :ref:`developer_policy`
 
    The LLVM project's policy towards developers and their contributions.