Make the categories section of the timeline view resizeable. #78
Description
Often times the categories section of the timeline contains more rows than there is space to render, resulting in a scroll bar on the right hand side.
It would be great if the user could see all of the categories rows without scrolling. One way to achieve this might be to make the spacer in between categories and events (div with class name 'glimpse-tl-row-spacer') draggable up/down to resize the two areas.
