Suggest to support custom labels in sizelegend

[gepcel]

For now, sizelegend can generate legend of sized markers, using the size of markers as labels, seems no other ways to use custom labels, unless there's some way that I don't know.

I suggest supporting custom labels. Like the following example:

import ultraplot as pplt
from legendkit import legend
fig,ax=pplt.subplots(refwidth=2.2,refheight=1)
ax.sizelegend([10,20,60],loc='ll',ncols=1, title="Ultraplot") # labels=['<10', '10-20', '20-60']
legend(ax=ax[0],loc='lower right', title='Custom Labels',
 legend_items=[
 ('o', '<10', {'ms': 1, 'c':'r'}),
 ('o', '10-20', {'ms': 2, 'c':'r'}),
 ('o', '20-60', {'ms': 6, 'c':'r'}),
])
ax.axis('off')

[cvanelteren]

It is possible with entrylegend

fig, ax = uplt.subplots()

ax.entrylegend(
 [
 {"label": "Small sample", "m": "o", "ms": 6},
 {"label": "Large sample", "m": "o", "ms": 12},
 ]
)
fig.show()

but that gets old pretty quick; can add this np