1.17.0: 24-bit color support

• introduced: 24-bit color support, detected by term.number_of_colors == 1 << 24, and 24-bit
  color foreground method color_rgb and background method
  on_color_rgb, as well as 676 common X11 color attribute names are now
  possible, such as term.aquamarine_on_wheat, #60.
• introduced: term.move_xy, recommended over built-in move capability, as the return
  positional arguments, (x, y) match the return value of get_location,
  and all other common graphics library calls, #65.
  values over the bterm.move.
• introduced: move_up`, move_down, move_left, move_rightwhich are strings that move the cursor one cell in the respective direction, are now also callables for moving *n* cells to the given direction, such asterm.move_right(9)``, .
• bugfix: prevent error condition, ValueError: underlying buffer has been detached in rare
  conditions where sys.stdout has been detached in test frameworks, #126.
• bugfix: off-by-one error in :meth:get_location, now accounts for %i in
  cursor_report, #94.
• bugfix split_seqs and related functions failed to match when the color index
  was greater than 15, #101.
• bugfix: Context Managers, fullscreen, hidden_cursor, and
  keypad now flush the stream after writing their sequences.
• bugfix: chr(127), \x7f has changed from keycode term.DELETE to the more common
  match, term.BACKSPACE, #115 by @jwezel.
• deprecated: the direct curses move() capability is no longer recommended, suggest to use
  move_xy(), which matches the return value of .get_location.
• deprecated: superscript, subscript, shadow, and dim are no longer "compoundable"
  with colors, such as in phrase Terminal.blue_subscript('a'). These attributes are not
  typically supported, anyway. Use Unicode text or 256 or 24-bit color codes instead.
• deprecated: additional key names, such as KEY_TAB, are no longer "injected" into the curses
  module namespace.
• deprecated: curses.setupterm is now called with os.devnull as the file descriptor, let us know if this causes any issues! :ghissue:59.
• deprecated: inkey no longer raises RuntimeError when stream
  is not a terminal, programs using Terminal.inkey may block indefinitely if a keyboard is
  not attached, #69.
• deprecated: using argument _intr_continue to method kbhit, behavior is as
  though such value is always True since 1.9.