Fix compilation and README of 2006/borsanyi

The Makefile needs -lpthread because not all systems implicitly link it
in. I tentatively noted this fix in the README.md but I'm not sure about
it as it's nothing special at all.

Format fix README.md. I note that I could not add <>s to the email
address as for some reason (in particular the dot in the email early on)
caused rdiscount (or I think - vim syntax certainly had a problem).

2006/borsanyi/Makefile

@@ -73,7 +73,7 @@ CFLAGS= ${CSTD} ${CWARN} ${ARCH} ${CDEFINE} ${CINCLUDE} ${OPT}
 
 # Libraries needed to build
 #
-LIBS=
+LIBS= -lpthread
 
 # C compiler to use
 #