Country view only displays two values on X axis

[jtg567]

JO and VU are only country codes shown at https://moz-distribution-viewer.herokuapp.com/chart/9/

Using FF "version": "50.0.2" release on Windows 10, fwiw

[robhudson]

Something appears to be broken with both the chart axis display (not all country codes are displayed) and the hover tooltips which do not work. I'm seeing JS console errors.

Flagging frontend devs @spasovski and @openjck

[rafrombrc]

For non-numeric, taxonomical values we want to show the N (15-20, probably) most popular values along the X-axis and use "other" to represent the long tail.

[openjck]

For non-numeric, taxonomical values we want to show the N (15-20, probably) most popular values along the X-axis and use "other" to represent the long tail.

Great! We can do that in #157. Separately from that, we might want to use this issue to figure out why only two labels are showing up here.

[openjck]

As it turns out, categorical charts are limited to 3 x-axis ticks. Showing more would be fine in this chart, but would cause labels to overlap in other charts.

So, this will go hand-in-hand with #163 (tilted labels) and #157 (group multiple data points into "other"). You could even call them dependencies. Once they're done, there may not be anything else to do.