message: Fix issue with back_color_erase
  back_color_erase should not set flags like bold, underline, etc.
diff: @@ -1417,7 +1417,9 @@ impl ansi::Handler for Term {
  #[inline]
  fn clear_line(&mut self, mode: ansi::LineClearMode) {
  trace!("clear_line: {:?}", mode);
  - let template = self.cursor.template;
  + let mut template = self.cursor.template;
  + template.flags ^= template.flags;
  +
  let col = self.cursor.point.col;
  match mode {
  @@ -1455,7 +1457,9 @@ impl ansi::Handler for Term {
  #[inline]
  fn clear_screen(&mut self, mode: ansi::ClearMode) {
  trace!("clear_screen: {:?}", mode);
  - let template = self.cursor.template;
  + let mut template = self.cursor.template;
  + template.flags ^= template.flags;
  +
  match mode {
  ansi::ClearMode::Below => {
  for cell in &mut self.grid[self.cursor.point.line][self.cursor.point.col..] {
  