[Feature Request] Multiple Marks

[si-phi]

Totally possible I'm an idiot here, but does this support multiple marks? I enjoy this package a lot but I can't seem to figure out how to get multiple marks to be used.

Example snippet of how I'd expect this to work:

`from chart import bar

x = [3,100]
y = ['useful things', 'useless things']

bar(x,y,mark=['🍑','🔊'])`