Allow asynchronous loading of CoinWidget

[q--]

Currently, CoinWidget needs to wait until the coin.js script is loaded, blocking the loading of a page.

<script src="coin.js"></script>
<script>
//Synchronous: the script needs to be loaded before this function can be called and the widget will be created at the place where the function is called. It isn't possible to call it after page load.
CoinWidgetCom.go({

    /* make sure you update the wallet_address or you will not get your donations */
    wallet_address: "122MeuyZpYz4GSHNrF98e6dnQCXZfHJeGS"

    , currency: "bitcoin"
    , counter: "count"
    , alignment: "bl"
    , qrcode: true
    , auto_show: false
    , lbl_button: "Donate"
    , lbl_address: "Donate Bitcoin to this Address:"
    , lbl_count: "donations"
    , lbl_amount: "BTC"
});
</script>

With the new code, it will be possible to do it as follows:

<span id='put_coinwidget_here'></span>
<!--The rest of the HTML document-->
Bottom of the page:
<script src='coin.js'></script>
//Asynchronous: replace an element with the CoinWidget
CoinWidgetCom.go({

    /* make sure you update the wallet_address or you will not get your donations */
    wallet_address: "122MeuyZpYz4GSHNrF98e6dnQCXZfHJeGS"

    , currency: "bitcoin"
    , counter: "count"
    , alignment: "bl"
    , qrcode: true
    , auto_show: false
    , lbl_button: "Donate"
    , lbl_address: "Donate Bitcoin to this Address:"
    , lbl_count: "donations"
    , lbl_amount: "BTC"
}, "#put_coinwidget_here");

Edit: The old way still works, by the way.
Another edit: The 2nd argument can be one of the following:

1. A reference to an HTML element; e.g. var element=document.body.firstChild;CoinWidgetCom.go({},element);
2. A jQuery wrapper for an HTML element; e.g. var element=$("#test");CoinWidgetCom.go({},element);
3. A list of HTML nodes, where the first one will be replaced; e.g. var elements=document.getElementsByClassName('test');CoinWidgetCom.go({},elements);
4. A string starting with a # followed by the ID of the element to be replaced; e.g. var element='#test';CoinWidgetCom.go({},element);
5. A string starting with a . followed by the class of the element to be replaced, where the first element with the class will be replaced; e.g. var element='.test';CoinWidgetCom.go({},element);
6. A string with the ID of the element to be replaced; e.g. var element='test';CoinWidgetCom.go({},element);