Fix icons for MIME types with "+"

fixes #99

HISTORY.md

@@ -1,6 +1,7 @@
 unreleased
 ==========
 
+  * Fix icons for MIME types with `+`
   * Fix text and json responses to match html sorting
   * Show font icon for more font types
   * Use 400 error on URI decode failure instead of 500

index.js

@@ -416,7 +416,7 @@ function iconLookup(filename) {
   // try by mime type
   if (icons[mimetype]) {
     return {
-      className: 'icon-' + mimetype.replace('/', '-'),
+      className: 'icon-' + mimetype.replace('/', '-').replace('+', '_'),
       fileName: icons[mimetype]
     };
   }

test/test.js

@@ -386,6 +386,7 @@ describe('serveIndex(root)', function () {
         .expect(/icon-default/)
         .expect(/icon-directory/)
         .expect(/icon-image/)
+        .expect(/icon-image-svg_xml/)
         .expect(/icon-txt/)
         .expect(/icon-application-pdf/)
         .expect(/icon-video/)