Minimum column width support. Support for the "noWhiteSpace" option in the tablewriter package.

[sheppe]

Added code and tests.

Setting the minimum column width will ensure that all outputted columns are at least that number of characters wide (plus cell padding). It makes some tables easier to read.

The tablewriter package now includes a noWhiteSpace option, which I added to the pretty tables options too.

There's one additional function that isn't used at the moment that made it into the commit as well.