revise curses_raw_print()

For curses, behave like tty by keeping a count of messages issued via
raw_print, then if that is non-zero issue a prompt and require the
player to acknowledge them before it erases the screen.  Mainly so
that complaints during RC file processing will be seen.

For tty, force getret() to be an unconditional routine instead of
sometimes a routine, sometimes a macro which calls another routine.

doc/fixes3-7-0.txt

@@ -2097,6 +2097,9 @@ curses: change petattr attributes, dropping support for curses-only ones
 curses: swap the grey and no-color color initialization
 curses: allow changing default colors with the 'palette' config option
 	(only if compiled with CHANGE_COLOR)
+curses: if messages have been issued during start-up (for instance, warnings
+	about issues in run-time config file), prompt user to press <return>
+	so that they can be read before curses erases the screen
 macOS: Xcode project was failing to build if the path to the NetHack source
 	tree contained a space; the issue was within some shell script code
 	contained within the project