and thus use random build flags (and often override our default CFLAGS)
for consistency enforce CMAKE_BUILD_TYPE:String=Release by default, and
CMAKE_BUILD_TYPE:String=Debug if DEBUG is set.
Provide a MODCMAKE_BUILD_SUFFIX variable added to SUBST_VARS, set to
either -debug.cmake or -release.cmake, will be used in some PLISTs
Went into an amd64 bulk build.
with/ok dcoppa@ sthen@