refactored tagging support

ChangeLog

asn1c/tests/check-43.c

asn1c/tests/check-65.c

libasn1compiler/asn1c_C.c

libasn1fix/asn1fix_internal.h

libasn1fix/asn1fix_tags.c

libasn1fix/asn1fix_tags.h

skeletons/ANY.c

skeletons/BIT_STRING.c

skeletons/BMPString.c

skeletons/BOOLEAN.c

skeletons/ENUMERATED.c

skeletons/GeneralString.c

skeletons/GeneralizedTime.c

skeletons/GraphicString.c

skeletons/IA5String.c

skeletons/INTEGER.c

skeletons/ISO646String.c

skeletons/NULL.c

skeletons/NativeEnumerated.c