Centralize hop-by-hop header handling in the main mod_cache code. This change...

Centralize hop-by-hop header handling in the main mod_cache code. This change is a no-op -- i.e. we call the same code path as prior to the API renaming. However this is propably wrong; and we should have been cleansing the content-types all along

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@649179 13f79535-47bb-0310-9956-ffa450edef68