Log stderr and stdout to file

Depends on #32 
Similar to https://github.com/cargomedia/socket-redis/blob/master/lib/utils.js#L15

Add some debug logging.
I would gladly simplify this logging. 
- Let's only print input params on beggining and when creation fails (`wait` is also included in params, let's not do special case for it?). 
- Let's print out task (not params) on success - or I would totally ignored this message.
- Remove those infos? Is it really important to log these down with info level?