Refactor project infrastructure docs.

The goal is to re-orient the documentation as an introduction for new
contributors and a reference for all contributors.

Change-Id: I8702a5ace908c7618a6451bbfef7fc79b07429ff
Reviewed-on: https://review.openstack.org/30515
Reviewed-by: Elizabeth Krumbach Joseph <lyz@princessleia.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins

doc/source/custom_roles.py

@@ -0,0 +1,52 @@
+# Copyright 2013 OpenStack Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+# Most of this code originated in sphinx.domains.python and
+# sphinx.ext.autodoc and has been only slightly adapted for use in
+# subclasses here.
+
+# Thanks to Doug Hellman for:
+# http://doughellmann.com/2010/05/defining-custom-roles-in-sphinx.html
+
+from docutils import nodes
+
+def file_role(name, rawtext, text, lineno, inliner,
+              options={}, content=[]):
+    """Link a local path to a Github file view.
+
+    Returns 2 part tuple containing list of nodes to insert into the
+    document and a list of system messages.  Both are allowed to be
+    empty.
+
+    :param name: The role name used in the document.
+    :param rawtext: The entire markup snippet, with role.
+    :param text: The text marked with the role.
+    :param lineno: The line number where rawtext appears in the input.
+    :param inliner: The inliner instance that called us.
+    :param options: Directive options for customization.
+    :param content: The directive content for customization.
+    """
+
+    ref = 'https://github.com/openstack-infra/config/blob/master/%s' % text
+    node = nodes.reference(rawtext, text, refuri=ref, **options)
+    return [node], []
+
+
+def setup(app):
+    """Install the plugin.
+
+    :param app: Sphinx application context.
+    """
+    app.add_role('file', file_role)
+    return