Merge r1364695, r1369477, r1369808, r1370288, r1370225, r1370763, r1371684 from trunk:

mod_lbmethod_heartbeat, mod_heartmonitor: Respect DefaultRuntimeDir/
DEFAULT_REL_RUNTIMEDIR for the heartbeat storage file.


core: Respect DefaultRuntimeDir/DEFAULT_REL_RUNTIMEDIR for the
scoreboard (ScoreBoardFile).


The Pidfile directive and ap_log_pid()/ap_remove_pid()/ap_read_pid()
now respect DefaultRuntimeDir


Mutex directive: finish support of DefaultRuntimeDir

a partial conversion was made in r1299718, but I'm not
sure when that change is effective


mod_socache_shmcb and mod_socache_dbm: finish support of
DefaultRuntimeDir

a partial conversion was made in r1299718, affecting cases
where no filename was specified


mod_slotmem_plain: make the "filename" key relative to
DefaultRuntimeDir if not absolute

mod_slotmem_plain does not externalize or check the full path
in any way, so this change is just for consistency with other
modules which build paths to run-time artifacts.


make LDAPSharedCacheFile relative to DefaultRuntimeDir

Submitted by: trawick
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1373105 13f79535-47bb-0310-9956-ffa450edef68