#5 func write_email works weird.

[Kibum Han]

When using readdbx in libdbx-1.0.3, I met segmentation
fault. The problem was in "void write_email(FILE *f,
char *body)" function.
Current version of the function processes one whole
line and one more character(the first character of a
next line) for each while cycle. So when the function
meet something like "blah\r\n\0unknown_world...", it
misses '\0' and enters an unknown world, which causes
seg fault some time.

[Kibum Han]