TH used on TBODY rows looks ugly

[dyve]

Thanks for using the select[multiple] fix.

Table headers (without fix) are ugly when used horizontally, like this:

http://jsbin.com/igufoc/4

The "big bottom border" styling should only be applied to TH inside THEAD and TFOOT, and possible also to TD inside THEAD and TFOOT. It's more of a THEAD/TFOOD property than a TH property.

[JakeWharton]

Just ran into this as well. Had to apply custom styles to the <th> anyway so was able to mitigate but having it fixed in the framework for the default shouldn't be too hard.

Relates to/dupes #316.

[mdo]

Closing since it's a dup.