Bucks chain constructor.
@name Bucks
@constructor
function Bucks(params) {
        this._tasks = [];
        this._taskcount = 0;
        this._results = [];
        this.callback = none;
        this.failure  = none;
        this._alive = true;
        this._interrupt = false;
        this.__id = uid();
        Bucks.living[this.__id] = this;
        this.initialize(params);
    }