Add vainminer script

[magdy122]

I am pretty sure that in older versions of nextgen (probably during mc 1.20) there was a feature called vainminer (as I remmber) here what it did
When you enable it you can punch and block and it will automatically mine all of the same kind of block that is connected to it and it was helpful when you have haste or high efficiency pick . I don't know why they removed it but I will be glad if it came back .