Support wider legends for longer names

[colinbrislawn]

This is an edge case for when the legend levels, say for colors, are much longer.

The Example metadata for Vizard uses a group with very short names, so this issue does not appear:

sample_name	group	x	y	a	b
#q2:types	categorical	numeric	numeric	numeric	numeric
sample01	aa	4	6	1	1
sample02	aa	5	9	2	2
sample03	aa	3	1	3	3
sample04	aa	5	3	4	5
sample05	aa	5	7	5	8
sample06	bb	2	4	1	10

With longer levels, the text is cut off.
example.qzv file

[colinbrislawn]

One possible fix is just adding a wider labelLimit

"legends": [
    {
      ...
      "labelLimit": 800,