Build pdf docs

This follows the instructions [1] in an attempt to build pdf docs.

The goal is described as docs that get made, not necessarily
perfect docs. This gets that.

[1] https://etherpad.openstack.org/p/train-pdf-support-goal

Change-Id: Icf7c22bf9d1de6fb2a74a756c370930d4c00b0b9
Story: 2006110
Task: 35396

doc/source/conf.py

@@ -53,3 +53,13 @@ html_theme = 'openstackdocs'
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.
 html_last_updated_fmt = '%Y-%m-%d %H:%M'
+
+# -- Options for LaTeX output -------------------------------------------------
+
+# Grouping the document tree into LaTeX files. List of tuples
+# (source start file, target name, title, author, documentclass
+# [howto/manual]).
+latex_documents = [
+    ('index', 'doc-os-traits.tex', u'os-traits Documentation',
+     u'OpenStack Foundation', 'manual'),
+]

tox.ini

@@ -28,6 +28,15 @@ commands =
   rm -rf doc/build
   sphinx-build -W -b html doc/source doc/build/html
 
+[testenv:pdf-docs]
+basepython = python3
+deps = {[testenv:docs]deps}
+whitelist_externals =
+  make
+commands =
+  sphinx-build -W -b latex doc/source doc/build/pdf
+  make -C doc/build/pdf
+
 [testenv:releasenotes]
 basepython = python3
 deps =