Rename tui_suppress_output

This patch renames tui_suppress_output to the more descriptive
tui_batch_rendering.  This code was never really correct, and was
based on a misunderstanding of the curses API.  The updated comments
describe the intended use of this class.

This also removes the erroneous tui_win_info::no_refresh.
wnoutrefresh does not prevent any output; rather, it copies from one
curses buffer to another but (unlike woutrefresh) without then
flushing to the screen.

tui_batch_rendering now works in the correct way: calling doupdate in
the destructor of the outermost instance, thus batching all screen
output until that point.

The patch adds instantiations of tui_batch_rendering to various spots,
to make sure it is active when refreshing.

gdb/python/py-tui.c

@@ -180,6 +180,8 @@ tui_py_window::~tui_py_window ()
 void
 tui_py_window::rerender ()
 {
+  tui_batch_rendering batch;
+
   tui_win_info::rerender ();
 
   gdbpy_enter enter_py;
@@ -206,6 +208,8 @@ tui_py_window::rerender ()
 void
 tui_py_window::do_scroll_horizontal (int num_to_scroll)
 {
+  tui_batch_rendering batch;
+
   gdbpy_enter enter_py;
 
   if (PyObject_HasAttrString (m_window.get (), "hscroll"))
@@ -220,6 +224,8 @@ tui_py_window::do_scroll_horizontal (int num_to_scroll)
 void
 tui_py_window::do_scroll_vertical (int num_to_scroll)
 {
+  tui_batch_rendering batch;
+
   gdbpy_enter enter_py;
 
   if (PyObject_HasAttrString (m_window.get (), "vscroll"))
@@ -242,6 +248,8 @@ tui_py_window::resize (int height_, int width_, int origin_x_, int origin_y_)
 void
 tui_py_window::click (int mouse_x, int mouse_y, int mouse_button)
 {
+  tui_batch_rendering batch;
+
   gdbpy_enter enter_py;
 
   if (PyObject_HasAttrString (m_window.get (), "click"))
@@ -258,6 +266,8 @@ tui_py_window::output (const char *text, bool full_window)
 {
   if (m_inner_window != nullptr)
     {
+      tui_batch_rendering batch;
+
       if (full_window)
 	werase (m_inner_window.get ());