Move CI docs from contributor guide into new CI guide

Creates a new CI guide in the index and moves all the ci docs
from under the contributor index where they currently live.  This makes
it easier to find CI related docs and also makes the contributor guide
index significantly shorter and so again easier to navigate for newcomer

Change-Id: I8a2c6df43e23bed7572cc81929d0086335f6eb7a
Related-Bug: #1804642

doc/source/ci/ci_primer.rst

@@ -25,7 +25,7 @@ submission merges. This then means that the job is broken in subsequent check ru
 Non tripleo-projects are not gated in tripleo. The promotion jobs
 represent the point at which we take the latest built tripleo packages and the
 latest built non-tripleo projects packages (like nova, neutron etc) and test these together.
-For more information about promotions refer to :doc:`Promotion Stages</contributor/stages-overview>`
+For more information about promotions refer to :doc:`Promotion Stages</ci/stages-overview>`
 
 Where do tripleo-ci jobs live
 -----------------------------
@@ -126,7 +126,7 @@ Where do tripleo promotion jobs live
 
 The tripleo promotions jobs are not defined in the tripleo-ci but instead live
 in the rdo-jobs_ repository. For more information about the promotion pipeline
-in TripleO refer to the :doc:`Promotion Stages</contributor/stages-overview>`
+in TripleO refer to the :doc:`Promotion Stages</ci/stages-overview>`
 
 Similar to the tripleo-ci jobs, they are defined in various files under the
 rdo-jobs-zuul.d_ directory and the job definitions look very similar to the

doc/source/ci/index.rst

@@ -0,0 +1,12 @@
+TripleO CI Guide
+================
+
+.. toctree::
+  :maxdepth: 2
+  :includehidden:
+
+  ci_primer
+  reproduce-ci
+  check_gates
+  dlrn-promoter-overview
+  stages-overview

doc/source/contributor/index.rst

@@ -7,10 +7,4 @@ TripleO Contributor Guide
 
   new_developers
   contributions
-  reproduce-ci
-  ci_primer
-  check_gates
-  dlrn-promoter-overview
-  stages-overview
-
 .. include:: ./squads.rst

doc/source/index.rst

@@ -16,6 +16,15 @@ Contributor Guide
   contributor/index
   developer/index
 
+Tripleo CI Guide
+----------------
+
+.. toctree::
+  :maxdepth: 3
+  :includehidden:
+
+  ci/index
+
 Install Guide
 -------------