Use a macro to indicate the space character substitution.

Use a macro to indicate the space character substitution.
It is somewhat safer to avoid non-ASCII characters in the source files
so avoid potential encoding issues on non-English platforms. And we may
as well use the # char as anything else. Macroified all usage of this
character and cleaned the errors reported by gcc for unchecked results.
Use fseek rather than reopening the wordlist file to start again.

Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>