function ok( value, msg ) {
	/* eslint-disable no-invalid-this */
	this._assert( !!value, {
		'message': msg || 'should be truthy',
		'operator': 'ok',
		'expected': true,
		'actual': value
	});
}
Asserts that a `value` is truthy.

@private
@param {*} value - value
@param {string} [msg] - message