Some labels are not showing up on treemap visualization

[mkchandler]

Investigate why some labels do not show up when zooming in to various levels. Sometimes I think it is because of the small size, but other times it seems like it should be showing.

This can be tested by looking at the sandbox/zoomable.html file.

[jagthedrummer]

I narrowed the problem down to this line: https://github.com/codeforokc/openbudgetokc/blob/master/sandbox/zoomable.html#L295

Basically if we detect that the label length is wider than the box that we're drawing it in then we hide the text. I played with it a bit to try to get the text to display and for the overflow of the box to hide whatever parts won't fit, but it seems that overflow inside of svg doesn't really work.

Conceptually I think we want to allow part of the text to show, and hide the parts that overflow the box. I'm not entirely sure how to approach that on the implementation side. Maybe something to do with clipping paths inside the svg?

[mkchandler]

We could also do a popover similar to how Oakland does: http://openbudgetoakland.org/2015-17-proposed-budget-tree.html#fy15-16.expense.fy15-16