mod_cache: try to use the key of a possible open but stale cache entry
if we have one in cache_try_lock(). PR 50317

Submitted by: Ruediger Pluem


git-svn-id: http://svn.apache.org/repos/asf/httpd/httpd/trunk@1597533 13f79535-47bb-0310-9956-ffa450edef68
Doxygen fix + reorg to match how other header files are built

git-svn-id: http://svn.apache.org/repos/asf/httpd/httpd/trunk@1597639 13f79535-47bb-0310-9956-ffa450edef68
Rename module name in doxygen + partly revert r832442 which skipped doxygen doc generation for 'mod_watchdog.h'

git-svn-id: http://svn.apache.org/repos/asf/httpd/httpd/trunk@1597642 13f79535-47bb-0310-9956-ffa450edef68