Fixed alex regex bug.

I wrote this patch to address an issue with how bnfc treats \n and \t codes in regular expressions destined for alex to parse.

token Word        ( (char - [" \n\t=;<|'\"\\"])+ ) ;

Given the above statement, bnfc will generates the following incorrect regular expression in the alex input file...

($u # [\  \
 \    \= \; \< \| \' \" \\]) + { tok (\p s -> PT p (eitherResIdent (T_Word . share) s)) }


It would be better, if it generated this instead:
 ($u # [\  \n \t \= \; \< \| \' \" \\]) + { tok (\p s -> PT p (eitherResIdent (T_Word . share) s)) }