* tags.h (scm_tags, scm_tc8_tags, scm_tc9_flag, scm_tc8_flag,
scm_tc8_isym): Renamed scm_tags to scm_tc8_tags. Renamed
scm_tc9_flag to scm_tc8_flag. Introduced new identifier
scm_tc8_isym. Defined tc8-tags relative to scm_tc3_imm24.
Defined the tc8-tag for flags to be 0x04, which will mean that
SCM_BOOL_F will also have the value 0x04 instead of 0x013c. Due
to the reduced number of bits and the simpler bit pattern for
SCM_BOOL_F, certain machines may be able to use more efficient
processor instructions to deal with SCM_BOOL_F.
(SCM_ITAG9, SCM_MAKE_ITAG9, SCM_ITAG9_DATA): Removed. These have
never been defined in a released version, thus no need to
deprecate them.
(SCM_IFLAGP, SCM_MAKIFLAG, SCM_IFLAGNUM): Flags now use tc8
instead of tc9 tags.
(SCM_ISYMP, SCM_MAKISYM, SCM_ISYMNUM): Isyms now use tc8 instead
of tc9 tags.
(SCM_MAKSPCSYM): Removed. It is almost impossible that user code
could have used this definition.
(SCM_IM_AND, SCM_IM_BEGIN, SCM_IM_CASE, SCM_IM_COND, SCM_IM_DO,
SCM_IM_IF, SCM_IM_LAMBDA, SCM_IM_LET, SCM_IM_LETSTAR,
SCM_IM_LETREC, SCM_IM_OR, SCM_IM_QUOTE, SCM_IM_SET_X): Now encoded
as isyms, as special isyms don't exist any more.