Fix json when calling the stats command

[anselal]

Due to a missing comma in the stats command output, the output cannot be parsed as a json.
This is simply fixed by replacing '}{' with '},{'

This fixes #4

[johndpope]

@tsileo - please merge

[anselal]

@johndpope Just grab a copy of this https://github.com/anselal/antminer-monitor/blob/master/lib/pycgminer.py
I added support for both Python 2 & 3 too.

Also check out the project if you are into mining crypto !!!