Implement PSR-3 logging interface

[estebangarcia]

I'm integrating this library on an HTTP API using Laravel. The "echo" style logging would show up sometimes on the HTTP Responses, breaking the JSON parsing for the clients.

I created a simple PS3 logger that echoes the messages called "EchoLogger" and modified the constructor to be able to override it for anyone that would like to use a different LoggingInterface.

[ePascalC]

Hi @estebangarcia , I like the use of echologger, but not everybody is using composer for using this binance api php file. So people that just use the php file in their environment would get an error as they might not have the psr logger.
In fact most of those 'echo' should maybe throw an error and not just echo things...

[dmzoneill]

needs rebase