Improve instructions/alt code for 1988/spinellis

There is no need to compile to 'runme': the way I designed the alt code
is so that it can be compiled and used exactly like the original entry.
Since the original entry need not compile to another file neither does
the alt version. It just compiles to spinellis.alt instead. (Perhaps
both should compile to something else though?)

The instructions of how to build/how to use in the README.md file have
been fixed and improved (it referred to the old way). The alt code
subsections have been added as well.

I also added to spinellis.alt.c #include <stdlib.h> as it's not a
one-liner anyway and this way system(3) is available without worrying
about warnings. The -Wno-everything still remains there in the system(3)
call in case there is a problem with the code that is typed in (though
that's not been tested either way).

1988/spinellis/Makefile

@@ -130,20 +130,21 @@ all: data ${TARGET}
 ${PROG}: ${PROG}.c input.txt
 	@${RM} -f $@
 	@echo
-	@echo "Hello, world!  To compile this IOCCC winner, we need you to take change."
+	@echo "Hello, world!  To compile this IOCCC winner, we need you to take charge."
 	@echo
-	@echo "IMPORTANT NOTE:"
+	@echo "IMPORTANT NOTE: this entry is likely to NOT compile with some compilers"
+	@echo "like clang, NOR will it likely compile under macOS. In particular the"
+	@echo "the compiler must accept reading in input from /dev/tty. Where this is"
+	@echo "not possible, try this instead: "
 	@echo
-	@echo "	This entry is likely to NOT compile with some compilers like clang, NOR will it likely"
-	@echo "	to compile under macOS.  For those situations, try this instead:"
+	@echo "    make clobber alt"
 	@echo
-	@echo "	make clobber alt"
+	@echo "For hosts with a true gcc compiler, manually run the following command:"
 	@echo
-	@echo "For non-macOS hosts with a true gcc compiler, manually run the following command:"
+	@echo "    ${GCC} ${CFLAGS} ${PROG}.c -o $@ ${LDFLAGS}"
 	@echo
-	@echo ${GCC} ${CFLAGS} ${PROG}.c -o $@ ${LDFLAGS}
-	@echo
-	@echo "Next copy and paste (on a non-macOS host) the folowwing as input to the above command:"
+	@echo "Next copy and paste (on a non-macOS host/host with true gcc)"
+	@echo "the folowwing as input to the above command:"
 	@echo
 	@${CAT} input.txt
 	@echo
@@ -151,7 +152,9 @@ ${PROG}: ${PROG}.c input.txt
 	@echo
 	@echo "Finally run the program you have just compiled:"
 	@echo
-	@echo "./$@"
+	@echo "    ./$@"
+	@echo
+	@echo "Of course you may provide other C code if you wish, even typing it manually."
 	@echo
 
 # alternative executable
@@ -163,11 +166,11 @@ ${PROG}.alt: ${PROG}.alt.c input.txt
 	@${RM} -f $@ runme
 	${CC} ${CFLAGS} ${PROG}.alt.c -o $@ ${LDFLAGS}
 	@echo
-	@echo "Hello, world!  To compile this IOCCC winner, we need you to take change."
+	@echo "Hello, world!  To compile this IOCCC winner, we need you to take charge."
 	@echo
 	@echo "Run the following command:"
 	@echo
-	@echo "./$@"
+	@echo "   ./$@"
 	@echo
 	@echo "Next copy and paste the folowwing as input to the above command:"
 	@echo
@@ -175,9 +178,11 @@ ${PROG}.alt: ${PROG}.alt.c input.txt
 	@echo
 	@echo "After pasing the above, end input by providing an EOF (usually control-D)."
 	@echo
-	@echo "Finally run the this progrqm:"
+	@echo "Finally run the program you have just compiled:"
 	@echo
-	@echo "./runme"
+	@echo "    ./$@"
+	@echo
+	@echo "Of course you may provide other C code if you wish, even typing it manually."
 	@echo
 
 # data files