Change 'may not compile to 'might not compile'

This is a subtle thing that I brought up on GitHub. Landon made the
change in many files but missed some in 1986 through 1989. I am aware of
a mass typo in the Makefiles but since some Makefiles are pending
changes I'm not doing that yet.

1986/bright/Makefile

@@ -195,7 +195,7 @@ alt: ${DATA} ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1986/stein/Makefile

@@ -189,7 +189,7 @@ ${PROG}: ${PROG}.c
 
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	-${RM} -f a.out
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 	-${LN} $@ a.out

1987/hines/Makefile

@@ -190,7 +190,7 @@ alt: ${DATA} ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1987/lievaart/Makefile

@@ -195,11 +195,11 @@ alt: ${DATA} ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 ${PROG}2.orig: ${PROG}2.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1988/dale/Makefile

@@ -191,7 +191,7 @@ alt: data ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1988/isaak/Makefile

@@ -194,7 +194,7 @@ alt: data ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1988/westley/Makefile

@@ -191,7 +191,7 @@ alt: data ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files

1989/jar.1/Makefile

@@ -192,7 +192,7 @@ alt: data ${ALT_TARGET}
 	@${TRUE}
 
 ${PROG}.orig: ${PROG.orig}.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${RM} -f $@
 	${CP} jar.1.orig.sh $@
 	${CHMOD} +x $@

1989/jar.2/Makefile

@@ -190,7 +190,7 @@ alt: data ${ALT_TARGET}
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 ${PROG}.orig: ${PROG}.orig.c
-	@echo "NOTE: The original source may not compile using modern compilers."
+	@echo "NOTE: The original source might not compile using modern compilers."
 	${CC} ${CFLAGS} $< -o $@ ${LIBS}
 
 # data files