Slightly customize RTD theme to use Symfony's feel

The goal is not to match the symfony.com style, that would be wasting our time.
This introduces a couple customizations according to RTD's official extension
points, to have a bit more relatable feeling in the demo docs.

Author: wouterj

_build/_static/rtd_custom.css

@@ -0,0 +1,23 @@
+body {
+	font-family:Lucida Grande,Lucida Sans Unicode,Lucida Sans,Geneva,Verdana,sans-serif !important;
+}
+
+h1, h2, h3, h4, h5, h6 {
+	font-family:Georgia,Times New Roman,Times,serif !important;
+	line-height:1.2 !important;
+	margin-top:0 !important;
+	margin-bottom:.5em !important;
+}
+p, .rst-content li{
+	font-size:14px !important;
+	line-height:1.45 !important;
+}
+.wy-menu-vertical a {
+	font-size:14px !important;
+	padding-right:0 !important;
+}
+
+.highlight {
+	background:#1e2125 !important;
+    color:#fafafa !important;
+}

_build/_static/symfony-logo.svg

@@ -140,12 +140,15 @@
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 html_theme = "sphinx_rtd_theme"
-html_theme_path = ["_themes", ]
 
 # 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.
-#html_theme_options = {}
+html_theme_options = {
+    'logo_only': True,
+    'prev_next_buttons_location': None,
+    'style_nav_header_background': '#f0f0f0'
+}
 
 # Add any paths that contain custom themes here, relative to this directory.
 #html_theme_path = []
@@ -159,7 +162,7 @@
 
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
-#html_logo = None
+html_logo = '_static/symfony-logo.svg'
 
 # The name of an image file (within the static path) to use as favicon of the
 # docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
@@ -169,7 +172,8 @@
 # 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']
+html_static_path = ['_static']
+html_css_files = ['rtd_custom.css']
 
 # If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
 # using the given strftime format.