HandlerFeedGenerator: Add caching

handlers/handlerpageedit.cpp

@@ -101,6 +101,7 @@ Response HandlerPageEdit::handleRequest(PageDao &pageDao, std::string pagename,
 				pageDao.setCategories(pagename, cats);
 				this->database->commitTransaction();
 				this->cache->removePrefix("page:"); // TODO: overkill?
+				this->cache->removePrefix("feed:");
 			}
 			catch(const DatabaseException &e)
 			{