css: fixed font-family stable

css: fixed font-family

There is no 'sans' font-family, replaced with 'sans-serif'

--- a/mercurial/templates/static/style.css	Fri Apr 19 22:03:59 2013 -0700
+++ b/mercurial/templates/static/style.css	Sat Apr 20 22:09:17 2013 +0400
@@ -14,13 +14,13 @@
   background-color: #666;
   padding: 2pt;
   color: white;
-  font-family: sans;
+  font-family: sans-serif;
   font-weight: bold;
 }
 .navigate a {
   background-color: #ccc;
   padding: 2pt;
-  font-family: sans;
+  font-family: sans-serif;
   color: black;
 }
 

--- a/tests/test-hgweb-commands.t	Fri Apr 19 22:03:59 2013 -0700
+++ b/tests/test-hgweb-commands.t	Sat Apr 20 22:09:17 2013 +0400
@@ -1178,13 +1178,13 @@
     background-color: #666;
     padding: 2pt;
     color: white;
-    font-family: sans;
+    font-family: sans-serif;
     font-weight: bold;
   }
   .navigate a {
     background-color: #ccc;
     padding: 2pt;
-    font-family: sans;
+    font-family: sans-serif;
     color: black;
   }