Fix lingering tt -> code sphinx 1.3 changes, refs #175

Addresses tt -> code changes in nav and references. Bumps requirements to sphinx
1.3, thought that might not be necessary.

requirements.txt

@@ -1 +1 @@
-sphinx>=1.1
+sphinx>=1.3

sass/_theme_layout.sass

@@ -52,6 +52,12 @@
         padding: $gutter / 4 $gutter * 1.5
         &:hover
           background: darken($section-background-color, 15%)
+    code
+      border: none
+      background: inherit
+      color: inherit
+      padding-left: 0
+      padding-right: 0
   // On state for the first level
   li.on a, li.current > a
     color: $text-color

sass/_theme_rst.sass

@@ -196,7 +196,7 @@
     .xref, a &
       font-weight: bold
   // If the literal is inside an a tag, let's color it like a link
-  a tt
+  a tt, a code
     color: $link-color
   dl
     margin-bottom: $base-line-height