Adding ValueFormatter and LabelColor to BarChart

[jsheely]

Is your feature request related to a problem? Please describe.
The BreakdownChart has the ability to do ValueFormatter but Barchart does not.

Describe the solution you'd like
I 've added the ValueFormatter to the Barchart so that you can format numbers like 1234 -> 1,234

Additional context
I've also the ability to color the label of the Barchart label using a property

I have a PR ready for this but opening an issue as per request.

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Please upvote 👍 this issue if you are interested in it.

[jsheely]

I can split these into two separate issues if needed but for my project needs I wanted them both.

• The ValueFormatter seems inline with how the other class works and seems straight forward.
• The colorization using a property instead of relying on the [green] notation is a little more subjective.

Let me know your thoughts and I will adjust accordingly.