function nextWord() in parser.c might move the character pointer beyond the terminating zero of the string

When calling the function
void nextWord( register char* word, char** ch )
in the file parser.c with a syntactically incorrect string that begins with a " but ends
with the terminating zero (without corresponding "), the pointer *ch (and c) are moved beyond the
terminating zero of the string in the statement
        c++; // to eat last character

This bug might be a problem e.g. if a script file with the incorrect line
p f2 w3000 h1500 v360 n"TIFF_m
is parsed by ParseScript() in parser.c .

The problem can be solved by replacing this statement by
        if(0 != *c)
           c++; // to eat last character