Allow hide and move columns in MMC

[potosino]

Maybe this functionality is already there, I just don't know how to use it. But I would love to be able to hide or remove some of the columns that I don't always use in MMC. I would also like to be able to re-arrange the order in which the columns appear from left to right.

dAP is great...thanks for your hard work and for wanting to make it better.

[Spoon]

Funnily enough this is being written right now, expect it in the next beta.