Renamed "gotty" to "tio"

Renamed to "tio" because it is shorter and this new name also more
precisely reflects what the program is - a simple TTY terminal I/O
application.

"tio" can be considered short for terminal I/O or TTY I/O or a
combination of the two, whichever you prefer.

Also, wanted to avoid naming conflicts with other projects.

src/include/gotty/log.h

@@ -1,30 +0,0 @@
-/*
- * Go TTY - The Really Simple Terminal Application
- *
- * Copyright (c) 2014-2016  Martin Lund
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- */
-
-#ifndef LOG_H
-#define LOG_H
-
-void log_open(char *filename);
-void log_write(char c);
-void log_close(void);
-void log_exit(void);
-
-#endif