@vx/threshold needs to generate unique clippath ids

[techniq]

Currently Threshold is using the same threshold-clip-below and threshold-clip-above ClipPath ids which causes an issue when using more than 1 Threshold chart on a page:

We need to generate unique ids for each of these per instance.

[williaster]

irrespective of the issue, chart 2 looks pretty cool like that :) need to play with clip paths more.

[techniq]

@williaster It did actually :). This made it easier to see (chart 1 is showing accumulated values over a month), when they were daily it was more painful to track down the cause...

[hshoff]

@techniq just published @vx/threshold@0.0.174 with the id prop fix.