Improve how to define sleep time in 1985/lycklama

With Makefile variables one can just do for instance:

    make SLEEP=700 clobber alt

which will set the macro Z to 700.

1985/lycklama/Makefile

@@ -58,7 +58,7 @@ ARCH=
 
 # Defines that are needed to compile
 #
-CDEFINE= -DZ=500
+CDEFINE= -DZ=${SLEEP}
 
 # Include files that are needed to compile
 #
@@ -137,6 +137,12 @@ ${PROG}: ${PROG}.c
 alt: data ${ALT_TARGET}
 	@${TRUE}
 
+SLEEP=500
+
+${PROG}.alt: ${PROG}.alt.c
+	${CC} ${CFLAGS} -DZ=${SLEEP} $< -o $@ ${LDFLAGS}
+
+
 # data files
 #
 data: ${DATA}

1985/lycklama/README.md

@@ -12,7 +12,7 @@ make alt
 ```
 
 To see why we recommend the alternate version instead of the original version,
-see below and the [original code](#original-code) section.
+see below and the [Original code](#original-code) section.
 
 
 ### Try:
@@ -25,7 +25,7 @@ reconfigure it like:
 
 
 ```sh
-make CDEFINE+="-DZ=700" clobber alt
+make SLEEP=700 clobber alt
 ```
 
 which would set it at 700. Then, whether you use the default value or not, try: