* __scm.h (SCM_DEBUG_DEBUGGER_SUPPORT): New compile-time option.

	* __scm.h (SCM_DEBUG_DEBUGGER_SUPPORT): New compile-time option.

	* gc.card.c (scm_gc_marked_p): Fixed compiler warning when
	compiling with SCM_DEBUG==1 by moving definition behind prototype.

	* gc.card.c (scm_dbg_t_list_cell, scm_dbg_t_double_cell,
	scm_dbg_gc_marked_p, scm_dbg_gc_get_card, scm_dbg_gc_get_bvec,
	scm_t_list_cell_struct, scm_t_list_cell, scm_t_double_cell,
	scm_gc_marked_p, scm_gc_get_card, scm_gc_get_bvec): Fixed
	functions such that they check if the object is a non-immediate.
	Further, renamed identifiers to use the scm_dbg_ prefix and made
	their inclusion into the lib dependent of the
	SCM_DEBUG_DEBUGGER_SUPPORT compile time option.