ca option and reporting errors no ECONNREFUSED
ca option and reporting errors no ECONNREFUSED

I added the ```ca``` options to provide an array with the CAs that
winston-logstash secure socket accept, so it is provided to node client
secure socket connection.

I also added a checking in socket ```error``` listener to report to
transport eventEmitter when socket received an error different from
ECONNREFUSED

drinks/winston-logstash,jaakkos/winston-logstash,jaakkos/winston-logstash,ollyw/winston-logstash,ollyw/winston-logstash,drinks/winston-logstash