Add a crude scrollbar to user preferences and game list filters.

This is done with even more dumb on-resize handling. Tested lightly in Chrome, Edge, and IE, and it seemed to work well enough.

Helps #93, though I don't want to use the f-word just yet.

WebContent/cah.css

@@ -244,6 +244,10 @@ h2,h3,h4 {
   float: right;
 }
 
+#tab-preferences, #tab-gamelist-filters {
+  overflow-y: auto;
+}
+
 .chat {
   border: 1px solid black;
   left: -1px;

WebContent/js/cah.app.js

@@ -401,6 +401,8 @@ function app_resize() {
   $("#bottom").height(bottomHeight);
   $("#info_area").height(bottomHeight);
   $("#tabs").height(bottomHeight);
+  $("#tab-preferences").height(bottomHeight - 45);
+  $("#tab-gamelist-filters").height(bottomHeight - 45);
 
   // global chat
   do_app_resize(chat, log);