Implement a flag to display logger or not

[anouvel]

In a multi-part project (consider termcaps, parser, job control, hum). To remove the output of the logger for some part, implement a flag.

general : L_G 0x01
termcaps : L_T 0x02
parser : L_P 0x04
job : L_J 0x08

and call the logger like it :

log_info(L_P | L_T, "%s", "log message");

This will display messages for general (everytime), parser and terncaps, but not job control.