significantly
Modify the DEBUG and PINFO macros to return unless qof_log_check is
true. Replace almost all direct calls to g_debug and g_message with
DEBUG and PINFO respectively.
Track the highest logging level sent to qof_log_set_level to provide a
short-circuit return in qof_log_check. Remove setting GNC_MOD_TESTS to
QOF_LOG_DEBUG so that the short-circuit threshold isn't defeated by
always being DEBUG.
Net result: 33% improvement in xml load times.
This will avoid a ninja-build from picking up a config.h generated by the autotools build
(in the root build directory). Picking up the wrong config.h may lead to all kinds of
subtle issues if the autotools run was done with different options than the cmake run.
