Fix the problem regarding the location of linbox-config.h and the _LINBOX_LINBOX_CONFIG_H variable.
Fix the problem regarding the location of linbox-config.h and the _LINBOX_LINBOX_CONFIG_H variable.

linbox-team/linbox,linbox-team/linbox,linbox-team/linbox,linbox-team/linbox,linbox-team/linbox