abolition iso-2022: remove tvterm_parse_encoding()
abolition iso-2022: remove tvterm_switch_to_ISO2022()
abolition iso-2022: remove tvterm_is_ISO2022()
abolition iso-2022: fix tvterm_finish_otherCS()
abolition iso-2022: remove tvterm_set_default_encoding_iso2022()
abolition: JFB_OTHER_CODING_SYSTEM
abolition otherCS: remove tvterm_parse_otherCS()
abolition otherCS: remove tvterm_finish_otherCS()
abolition otherCS: remove tvterm_set_default_encoding_other()
abolition: JFB_OTHER_CODING_SYSTEM
abolition otherCS: remove tvterm_switch_to_otherCS()
abolition otherCS: remove tvterm_is_otherCS()
abolition otherCS: remove tvterm_put_otherCS_char()
abolition otherCS: remove tvterm_esc_designate_otherCS()
abolition otherCS: remove TCodingSystem
abolition: tvterm_{,re}_invoke_gx()
abolition iso-2022: remove IS_GL_AREA()
abolition iso-2022: remove IS_GR_AREA()
abolition iso-2022: remove strct TFontSpec
abolition iso-2022: fix struct TVterm