loadRunningEnvironment(setNodeEnv) {
        const env = this._cliConfig.get('running');

        if (!env) {
            throw new Error('This instance is not running.');
        }

        this.system.setEnvironment(env === 'development', setNodeEnv);
    }
Sets the environment of the system to the current running
environment of the CLI.

@param {bool} setNodeEnv If true, sets the NODE_ENV environment variable
              to the running environment

@method loadRunningEnvironment
@public