introduce switch for 'fancy scrolling'

doc/ncmpcpprc

@@ -116,6 +116,8 @@
 #
 #colors_enabled = "yes"
 #
+#fancy_scrolling = "yes"
+#
 #empty_tag_color = "cyan"
 #
 #header_window_color = "default"

src/ncmpcpp.cpp

@@ -719,11 +719,35 @@ int main(int argc, char *argv[])
 		
 		if (Keypressed(input, Key.Up))
 		{
-			wCurrent->Go(wUp);
+			if (!Config.fancy_scrolling && (wCurrent == mLibArtists || wCurrent == mPlaylistList || wCurrent == mEditorLeftCol))
+			{
+				wCurrent->SetTimeout(50);
+				while (Keypressed(input, Key.Up))
+				{
+					wCurrent->Go(wUp);
+					wCurrent->Refresh();
+					wCurrent->ReadKey(input);
+				}
+				wCurrent->SetTimeout(ncmpcpp_window_timeout);
+			}
+			else
+				wCurrent->Go(wUp);
 		}
 		else if (Keypressed(input, Key.Down))
 		{
-			wCurrent->Go(wDown);
+			if (!Config.fancy_scrolling && (wCurrent == mLibArtists || wCurrent == mPlaylistList || wCurrent == mEditorLeftCol))
+			{
+				wCurrent->SetTimeout(50);
+				while (Keypressed(input, Key.Down))
+				{
+					wCurrent->Go(wDown);
+					wCurrent->Refresh();
+					wCurrent->ReadKey(input);
+				}
+				wCurrent->SetTimeout(ncmpcpp_window_timeout);
+			}
+			else
+				wCurrent->Go(wDown);
 		}
 		else if (Keypressed(input, Key.PageUp))
 		{

src/settings.cpp

@@ -169,6 +169,7 @@ void DefaultConfiguration(ncmpcpp_config &conf)
 	conf.statusbar_color = clDefault;
 	conf.active_column_color = clRed;
 	conf.colors_enabled = true;
+	conf.fancy_scrolling = true;
 	conf.columns_in_playlist = false;
 	conf.header_visibility = true;
 	conf.statusbar_visibility = true;
@@ -501,6 +502,10 @@ void ReadConfiguration(ncmpcpp_config &conf)
 			{
 				conf.colors_enabled = v == "yes";
 			}
+			else if (it->find("fancy_scrolling") != string::npos)
+			{
+				conf.fancy_scrolling = v == "yes";
+			}
 			else if (it->find("playlist_display_mode") != string::npos)
 			{
 				conf.columns_in_playlist = v == "columns";

src/settings.h

@@ -115,6 +115,7 @@ struct ncmpcpp_config
 	Color active_column_color;
 	
 	bool colors_enabled;
+	bool fancy_scrolling;
 	bool columns_in_playlist;
 	bool set_window_title;
 	bool header_visibility;

src/window.cpp

@@ -226,6 +226,7 @@ void Window::Refresh(bool stub)
 void Window::Clear(bool stub)
 {
 	werase(itsWindow);
+	wrefresh(itsWindow);
 }
 
 void Window::Hide(char x) const