Add an option to make column header static

[jpetitcolas]

For instance, if I have a lot of numeric numbers such as:

It would be great to add the header columns to follow the scroll.

[fzaninotto]

Doesn't seem very straightforward: http://stackoverflow.com/questions/21168521/scrollable-table-with-fixed-header-in-bootstrap. But I agree, this would be a great enhancement.