Created ColorPicker example app

[jennalenoble]

This app uses Loading and ColorPicker component to change the bar colour of a histogram.

[AnnMarieW]

Another great example - thanks @jennalenoble :tada:

Same comments apply as in #138 regarding the dcc.Loading and code formatting with Black.

It would be good to add a comment to this line, because it's not super obvious what this does:

# Sets the default theme for the figures
pio.templates.default = "ggplot2"

@Coding-with-Adam - what do you think about using the new Partial Property Updates in this example?

[Coding-with-Adam]

@Coding-with-Adam - what do you think about using the new Partial Property Updates in this example?

Hi @AnnMarieW Thank you for the review. There is already a very similar example in the Dash docs and Tim is working on adding another one that updates marker colors of a graph. I think we can leave this as is. I will teach Jenna about the Patch next week because we definitely need a nice set of examples about that.

[Coding-with-Adam]

Very nice app @jennalenoble and amazing code for someone that just recently started learning Python.

Let me know if you have any questions implementing the comments I added, or if you need help with Black to format the code.

[jennalenoble]

Thanks so much for the feedback @AnnMarieW & @Coding-with-Adam! The recent commit incorporates the code changes and uses Black formatting in both files.

[Coding-with-Adam]

Thanks @jennalenoble .

@AnnMarieW can I merge this app or do you prefer to take one last look?