* misc.c (is_secured_filename): New.
* keydb.c (maybe_create_keyring)
* tdbio.c (tdbio_set_dbname)
* plaintext.c (handle_plaintext)
* openfile.c (copy_options_file, open_outfile)
* exec.c (exec_write)
* keygen.c (do_generate_keypair, gen_card_key_with_backup)
* sign.c (sign_file, clearsign_file)
* keyring.c (create_tmp_file, do_copy): Check for secured files
before creating them.
* keygen.c (print_status_key_created): s/unsigned char/byte/ due
to a strange typedef for RISC OS.  Noted by Stefan.