Make the handling of output and input formats consistent

Most of all, we needed to sort out which ones are binary and which
ones are text, and make sure they are treated accordingly and
consistently so

Reviewed-by: Tim Hudson <tjh@openssl.org>

apps/req.c

@@ -764,7 +764,8 @@ int req_main(int argc, char **argv)
 
     out = bio_open_default(outfile,
                            keyout != NULL && outfile != NULL &&
-                           strcmp(keyout, outfile) == 0 ? "a" : "w");
+                           strcmp(keyout, outfile) == 0
+                           ? AB(outformat) : WB(outformat));
     if (out == NULL)
         goto end;