Add patched sphinx_rtd_theme

There must be a cleaner way to do this... Currently, this theme is built
with:

--- a/sass/_theme_layout.sass
+++ b/sass/_theme_layout.sass
@@ -292,7 +292,7 @@
 .wy-nav-content
   padding: $gutter $gutter * 2
   height: 100%
-  max-width: 800px
+  max-width: 1000px
   margin: auto

 .wy-body-mask
@@ -354,13 +354,6 @@ footer
       height: 100%
       overflow: hidden

-+media($desktop-wider)
-  .wy-nav-content-wrap
-    background: rgba(0,0,0,.05)
-  .wy-nav-content
-    margin: 0
-    background: $section-background-color
-
 @media print
   .rst-versions, footer, .wy-nav-side
     display: none

and this on bower_components/wyrm/sass/wyrm_core/_wy_variables.sass

- $base-font-size:                      16px !default
+ $base-font-size:                      18px !default
  $base-font-family:                    "Helvetica Neue", Arial, sans-serif !default
  $base-font-family-bold:               bold
- $base-line-height:                    24px !default
+ $base-line-height:                    27px !default

_themes/sphinx_rtd_theme/searchbox.html

@@ -0,0 +1,9 @@
+{%- if builder != 'singlehtml' %}
+<div role="search">
+  <form id="rtd-search-form" class="wy-form" action="{{ pathto('search') }}" method="get">
+    <input type="text" name="q" placeholder="Search docs" />
+    <input type="hidden" name="check_keywords" value="yes" />
+    <input type="hidden" name="area" value="default" />
+  </form>
+</div>
+{%- endif %}