Inline webform elements missing form-inline class

Title says it all, the attached patch adds the missing class which produces OK results. It would be better IMHO to style the whole form with .form-horizontal to do it the Bootstrap way (we then need to remove the widht: 100% on all form-control input), but this doesn't fit well in the webform approach of setting the inline attribute at the component level.

Anyways, at the individual component level this patch works as I said.