Improve readline code:

don't flush if we change output stream;
   use readline from interrupt handler.


git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@85 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

H/yapio.h

@@ -283,10 +283,6 @@ void	STD_PROTO(plwrite,(Term,int (*)(int, int),int));
 /* grow.c */
 int  STD_PROTO(growstack_in_parser,  (tr_fr_ptr *, TokEntry **, VarEntry **));
 
-#ifdef HAVE_LIBREADLINE
-extern int in_readline;
-#endif
-
 #if HAVE_ERRNO_H
 #include <errno.h>
 #else