sock_printf_error(): factored out the 'huh?-stuff, added error report
log)
- use sock_printf() and sock_printf_error() if necessary (no need to
use sprintf())
- Moved and altered code to create, destroy and manipulate clients, screens
and widgets in an OO-like manner.
- Moved command execution code to a commands directory, splitting commands to
what subject they are concerned.
- Menus are temporary disabled while working on new menu structure.