I think updating log4js to to 2.5.2 has breaking changes

[aruiz-caritsqa]

When running kobold, I get the following error:

TypeError: log4js.getDefaultLogger is not a function
    at Base.extend.getSource (/Users/x/.nvm/versions/node/v6.10.1/lib/node_modules/kobold/lib/kobold.js:48:25)
    at new <anonymous> (/Users/x/.nvm/versions/node/v6.10.1/lib/node_modules/kobold/node_modules/preceptor-core/lib/utils.js:108:34)
    at koboldRunner (/Users/x/.nvm/versions/node/v6.10.1/lib/node_modules/kobold/index.js:18:10)
    at Object.<anonymous> (/Users/x/.nvm/versions/node/v6.10.1/lib/node_modules/kobold/resource/run.js:5:1)
    at Module._compile (module.js:570:32)

log4js seems to use [https://github.com/log4js-node/log4js-node]
const logger = log4js.getLogger('x');