Feature request: support json log files

[matanox]

Support for json log files such as the ones produced by winston, where each row in the log file is a json object.

This can work through a new command-line argument signaling the input should be assumed a json log file. Can just encapsulate the log rows, each row being a json object, as an array under a synthetic parent element named 'log' or 'object list' or anything else, prior to passing on to the existing formatting and display.