With this patch the debian bug 707109 can be avoided; as apxs2 returns noise in debian wheezy, using exec_program the variable gets assigned the STDERR instead of the proper value.
use execute_process instead of exec_program in FindAPACHE.cmake
See also mapserver/mapcache#104
trailing whitespace breaks build
use execute_process instead of exec_program in FindAPACHE.cmake (#4948)
also remove trailing whitespaces as they break builds
squashed and cherry-picked to the stable branch in 644d750