brianreavis/selectize.js — pull request #320 by sjhewitt (2014-03-04 18:58:54+00:00)
Title: optgroup_columns: set width as percentage

the calculated width did not take into account the scrollbar, so if a scrollbar exists, the last column flowed onto the next row.
This change sets the column width as a percentage, so the browser can layout the columns on the same row (it rounds the percentage down so that they fit slightly better)