Handle doc/requirements.txt

Change Ief487e1d20ea20facf398367ca03a6385182fb38 updated the PTI for doc
jobs and introduces doc/requirements.txt. Support that for requirements
syncing.

Change-Id: I147a129438ae370eb4c90ee93a634fa61cc179f4

.zuul.d/project-template.yaml

@@ -17,4 +17,5 @@
       - ^tools/.*-requires$
       - ^.*requirements.txt$
       - ^.*requirements-py[2,3].txt$
+      - ^doc/requirements.txt$
       - playbooks/requirements-check.yaml

README.rst

@@ -57,7 +57,8 @@ Solution
 The mechanics of the solution are relatively simple. We maintain a
 central list of all the requirements (``global-requirements.txt``)
 that are allowed in OpenStack projects. This is enforced for
-``requirements.txt``, ``test-requirements.txt`` and extras defined in
+``requirements.txt``, ``test-requirements.txt``,
+``doc/requirements.txt``, and extras defined in
 ``setup.cfg``. This is maintained by hand, with changes going through CI.
 
 We also maintain a compiled list of the exact versions, including transitive

openstack_requirements/project.py

@@ -132,6 +132,7 @@ def read(root):
     target_files = [
         'requirements.txt', 'tools/pip-requires',
         'test-requirements.txt', 'tools/test-requires',
+        'doc/requirements.txt'
     ]
     for py_version in (2, 3):
         target_files.append('requirements-py%s.txt' % py_version)

tools/cruft.sh

@@ -57,7 +57,8 @@ for PROJECT in $(cat projects.txt); do
             test-requirements-py3.txt \
             test-requirements.txt \
             tools/pip-requires \
-            tools/test-requires
+            tools/test-requires \
+            doc/requirements.txt
         do
             if [ -f $FILE ]; then
                 # Add diagnostic comments to aid debugging.