Increase clickable zone for column width adjustment & resizing

[#1]

The current column width adjustment control is about ~2 pixels wide when at 100% zoom.  Users find it very hard to adjust column size, often time miss-clicking and not getting the column width resizing option.  If the clickable zone was approximately twice the size, it would be far less finicky.

[#2]

agree, this is so frustrating when you are constantly resizing column widths that aren't sticky

[#3]

I agree, this has been something that's been an issue for a long time.