function vec3lerp(out, a, b, t, oa, ob) {
    var ax = a[oa];
    var ay = a[oa + 1];
    var az = a[oa + 2];
    out[0] = ax + t * (b[ob] - ax);
    out[1] = ay + t * (b[ob + 1] - ay);
    out[2] = az + t * (b[ob + 2] - az);

    return out;
}
Creates a quaternion from the given 3x3 rotation matrix.

NOTE: The resultant quaternion is not normalized, so you should be sure
to renormalize the quaternion yourself where necessary.

@param {quat} out the receiving quaternion
@param {mat3} m rotation matrix
@returns {quat} out
@function