Fix line overflows in PDF

modified: code/ch08/ex10-resilient/mph_drop.ex,
 code/ch08/ex7-talkingProcs/mph_drop.ex,
 code/ch08/ex8-linking/mph_drop.ex,
 code/ch08/ex9-trapping/mph_drop.ex,
 code/ch09/ex2-debug/mph_drop.ex,
 code/ch10/ex7-mnesia/mph_drop.ex

Required changing an example to use IO.write.