Switch documentation to alabaster theme

These are OpenDev docs now so the OpenStack theming doesn't quite fit.
Switch to Alabaster + OpenDev logo which is what we did with
infra-manual.

Change-Id: Id211e8e0b4dab7282fb5ca5fce494a028a826fba

doc/source/conf.py

@@ -2,6 +2,7 @@
 #
 # system-config documentation build configuration file
 
+import datetime
 import os
 import sys
 
@@ -16,7 +17,6 @@ sys.path.insert(0, os.path.abspath('.'))
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = ['custom_roles',
-              'openstackdocstheme',
               'zuul_sphinx']
 
 # We have roles split between zuul-suitable roles at top level roles/*
@@ -25,10 +25,6 @@ extensions = ['custom_roles',
 # roles).  Document both.
 zuul_role_paths = ['playbooks/roles']
 
-# openstackdocstheme options
-repository_name = 'opendev/system-config'
-use_storyboard = True
-
 # The suffix of source filenames.
 source_suffix = '.rst'
 
@@ -36,7 +32,8 @@ source_suffix = '.rst'
 master_doc = 'index'
 
 # General information about the project.
-copyright = u'2012-2018, OpenStack Infrastructure Team'
+project = u'OpenDev System Documentation'
+copyright = ('%d, OpenDev Contributors.' % datetime.date.today().year)
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
@@ -48,26 +45,18 @@ pygments_style = 'sphinx'
 
 # -- Options for HTML output ----------------------------------------------
 
+# This static content is used by the logo below
+html_static_path = [
+        '_static/',
+    ]
+
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
-html_theme = 'openstackdocs'
-
-# Theme options are theme-specific and customize the look and feel of a theme
-# further.  For a list of options available for each theme, see the
-# documentation.
-
-# To use the API Reference sidebar dropdown menu,
-# uncomment the html_theme_options parameter.  The theme
-# variable, sidebar_dropdown, should be set to `api_ref`.
-# Otherwise, the list of links for the User and Ops docs
-# appear in the sidebar dropdown menu.
-#html_theme_options = {'show_other_versions': True}
-
-# Add any paths that contain custom static files (such as style sheets) here,
-# relative to this directory. They are copied after the builtin static files,
-# so a file named "default.css" will overwrite the builtin "default.css".
-#html_static_path = ['_static/css']
+html_theme = 'alabaster'
 
+html_theme_options = {
+        'logo': 'opendev.svg'
+    }
 
 # -- Options for LaTeX output ---------------------------------------------