function mgf( t, mu ) {
	return addon( t, mu );
}
Evaluates the moment-generating function (MGF) for a degenerate distribution centered at `mu`.

@private
@param {number} t - input value
@param {number} mu - value at which to center the distribution
@returns {number} evaluated MGF

@example
var y = mgf( 1.0, 2.0 );
// returns ~7.389

@example
var y = mgf( 0.0, 2.0 );
// returns 1.0

@example
var y = mgf( -1.0, 2.0 );
// returns ~0.135

@example
var y = mgf( NaN, 2.0 );
// returns NaN

@example
var y = mgf( 1.0, NaN );
// returns NaN