Add guidelines/recommendations for organizers of LLVM Socials

Differential Revision: https://reviews.llvm.org/D61550

llvm-svn: 360651
diff --git a/llvm/docs/index.rst b/llvm/docs/index.rst
index b03e6b7..97193db 100644
--- a/llvm/docs/index.rst
+++ b/llvm/docs/index.rst
@@ -565,6 +565,21 @@
 * clang-bot - A `geordi <http://www.eelis.net/geordi/>`_ instance running
   near-trunk clang instead of gcc.
 
+Meetups and social events
+-------------------------
+
+.. toctree::
+   :hidden:
+
+   MeetupGuidelines
+
+Besides developer `meetings and conferences <https://llvm.org/devmtg/>`_,
+there are several user groups called
+`LLVM Socials <https://www.meetup.com/pro/llvm/>`_. We greatly encourage you to
+join one in your city. Or start a new one if there is none:
+
+:doc:`MeetupGuidelines`
+
 Community wide proposals
 ------------------------