[BUG] Handling two columns with the same name on .iplot()

[thomktz]

[cufflinks 0.17.3, plotly >= 4.1.1, used in VisualStudioCode notebooks]

Reproduce

To reproduce the bug, call .iplot() on a dataframe containing two columns with the same name

Description

The graph will appear very weird and not readable at all

Proposed solution

When two or more columns have the same name, automatically rename them "{x}_0", "{x}_1", or "{x} (0)", "{x} (1)"

I can work on this myself if others find the issue problematic and the solution relevant.