connections fd are now SOCK_NONBLOCK, so we do not have to wait until they are ready
Better treatement for EAGAIN errno
Now closing TCP connection at the end of life
Added global configuration struct
Added brokers and topic to config file
Added number_of_threads to global config
skip the select if is shutting down, so the exit is faster if there is many threads
added example n2kafka_config
Moved port to config struct
Deleted list management. Protected topic and some allocations.