Rewritten.

Rewritten.
(append_glyph): New.
(update_end): Turn cursor on only if selected window's
cursor_off_p flag is not set.
(TS_cursor_visible): Renamed from TS_visual_mode.
(TS_cursor_normal): Renamed from TS_end_visual_mode.
(TS_cursor_invisible):  New.
(term_init): Initialize TS_cursor_invisible.
(tty_hide_cursor): New.
(tty_show_cursor): New.
(update_end): Show tty cursor.
(update_begin): Hide tty cursor to prevent cursor flickering
during redisplays triggered by timers (stealth fontification).
(estimate_mode_line_height): New.
(estimate_mode_line_height_hook): New.
(OUTPUT_IF): Make replacement text have statement form.
(OUTPUT1_IF): Ditto.
(TS_italic_mode, TS_end_italic_mode): Removed.
(TS_bold_mode): Removed.
(TS_underscore_mode, TS_end_underscore_mode): Removed.
(TS_enter_bold_mode, TS_enter_dim_mode, TS_enter_blink_mode): New.
(TS_enter_reverse_mode): New.
(TS_enter_underline_mode, TS_exit_underline_mode): New.
(TN_magic_cookie_glitch_ul): New.
(TS_enter_alt_charset_mode, TS_exit_alt_charset_mode): New.
(TS_exit_attribute_mode): New.
(TN_max_colors, TN_max_pairs, TS_orig_pairs): New.
(TS_set_foreground, TS_set_background): New.
(reset_terminal_modes): Switch colors back to default.
(write_glyphs): Turn face on before writing text, turn it off
afterwards.
(insert_glyphs): Ditto.
(term_init): Initialize new terminal capability variables.
(turn_on_face): Turn a face on.
(turn_off_face): Turn a face off.
(global): Rewrite for new glyphs.