Updates and improvements to 2000/thadgavin

The alt code now allows one to quit early (in curses mode) and this
calls endwin() to restore terminal sanity. Due to the way the code is
designed the function which does that has to be defined three times but
only one has any code in it, that of the curses one. This means that
nodelay() is also called when initialising curses. At least at this time
the original entry does not have this feature and so one will have to
type 'reset' after they end the program to restore terminal sanity.

The alt code has been improved in another way too: now one does not have
to specify both macros at the command line when wishing to configure
only one of the programs. This is accomplished by #ifndef..#endif blocks
at the beginning of the file. That has not been done in other entries
but probably should be to help out.

The README.md file has been typo/format checked/fixed.

The FAQ has been updated as well: a question about how to use entries
that require curses has been added. This required some minor reordering
of the numbers but I believe that I got everything okay.

2000/thadgavin/Makefile

@@ -62,7 +62,7 @@ CDEFINE= -DZ=30 -DZS=150000
 
 # Include files that are needed to compile
 #
-CINCLUDE= -include unistd.h
+CINCLUDE= -include unistd.h -include stdlib.h
 
 # Optimization
 #
@@ -112,10 +112,10 @@ PROG= ${ENTRY}
 #
 OBJ= ${PROG}.o
 DATA=
-TARGET= ${PROG}
+TARGET= ${PROG} ${PROG}_sdl
 #
-ALT_OBJ= ${PROG}.alt.o
-ALT_TARGET= ${PROG}.alt
+ALT_OBJ= ${PROG}.alt.o ${PROG}.alt_sdl.o
+ALT_TARGET= ${PROG}.alt ${PROG}.alt_sdl
 
 
 #################
@@ -145,10 +145,10 @@ alt: data ${ALT_TARGET}
 ${PROG}.alt: ${PROG}.alt.c
 	${CC} ${CFLAGS} $< -o $@ ${LDFLAGS}
 
-
 ${PROG}.alt_sdl: ${PROG}.alt.c
 	${CC} ${CFLAGS} -DSDL `${SDL1_CONFIG} --cflags` $< -o $@ ${LDFLAGS} `${SDL1_CONFIG} --libs`
 
+
 # data files
 #
 data: ${DATA}