Widen section labels on swissen template

I noticed that on the swissen template, the word "experience" was a bit
too long to use as a section label. Given that this is a pretty short
word, and also a very common section label for résumés, I widened the
section labels from 16% of the total width to 20% (and reduced the width
of the main text area to match) for both html and pdf renderings.

templates/swissen/css/screen.css

@@ -82,12 +82,12 @@
     
     h3 {
         float: left;
-        width: 16%;
+        width: 20%;
     }
     
     h3+p {
         float: left;
-        width: 84%;
+        width: 80%;
     }
     
     ul li {
@@ -107,7 +107,7 @@
 
     ol {
         float: left;
-        width: 84%;
+        width: 80%;
         margin: .6em 0 0;
     }