Update thanks file wrt 2014/skeggs + add -ldl

When I got this entry to work apparently I never added a thanks for it
so this is now done.

Also to make the compilation more portable I added -ldl to the LDFLAGS.
This is something Yusuke Endoh did and although not necessary in the
systems I tried it since it uses dlsym() it's better to have it.

2014/skeggs/.gitignore

@@ -1,2 +1,7 @@
 prog
 prog.orig
+err
+static_assert
+t.c
+thread_local
+volatile

2014/skeggs/Makefile

@@ -74,7 +74,7 @@ CFLAGS= ${CSTD} ${CWARN} ${ARCH} ${CDEFINE} ${CINCLUDE} ${OPT}
 
 # Libraries needed to build
 #
-LDFLAGS=
+LDFLAGS= -ldl
 
 # C compiler to use
 #
@@ -154,7 +154,7 @@ everything: all alt
 ###############
 #
 clean:
-	${RM} -f ${OBJ} ${ALT_OBJ}
+	${RM} -f ${OBJ} ${ALT_OBJ} err static_assert t.c thread_local volatile
 	@-if [ -f indent.c ]; then \
 	    echo ${RM} -f indent.c; \
 	    ${RM} -f indent.c; \