Do not cache the front page and search results (#2433)

- This should avoid caching the from page for 30 minutes
    - The view can be inconsistent with the system state
        - different cookies
        - different messages
        - different projects
 - The same applies for search results
 - Other resources are hidden behind the 30 minutes cache interval

Author: tulinkry

opengrok-web/src/main/webapp/WEB-INF/web.xml

@@ -54,9 +54,17 @@
         <dispatcher>REQUEST</dispatcher>
     </filter-mapping>
     <filter-mapping>
-        <!-- Place this mapping last, so /* wildcard is only a fallback -->
         <filter-name>ExpiresHalfHourFilter</filter-name>
-        <url-pattern>/*</url-pattern>
+        <url-pattern>/history/*</url-pattern>
+        <url-pattern>/xref/*</url-pattern>
+        <url-pattern>/raw/*</url-pattern>
+        <url-pattern>/download/*</url-pattern>
+        <url-pattern>/diff/*</url-pattern>
+        <url-pattern>/more/*</url-pattern>
+        <url-pattern>/rss/*</url-pattern>
+        <url-pattern>/error</url-pattern>
+        <url-pattern>/enoent</url-pattern>
+        <url-pattern>/eforbidden</url-pattern>
         <dispatcher>REQUEST</dispatcher>
     </filter-mapping>
     <servlet>