Don't include development assets in Python package

[xhochy]

Is your feature request related to a problem? Please describe.

The dash-renderer sdist on PyPI is quite big large (2.3M compressed, 10M uncompressed) compared to the actual required components. This is due to at least the following files that shouldn't be required:

• dash_renderer.dev.js (3.9M)
• dash_renderer.dev.js.map (4.5M)
• dash_renderer.min.js.map (1.3M)

Describe the solution you'd like

Don't distribute files for development purposes in release artifacts. This would reduce the size of the package to 1/10 (200K compressed, 720K uncompressed).

Describe alternatives you've considered

As an alternative to not shipping the debug maps at all, you could also distribute them as separate -dbg packages. This would enable a user to get debug information but not having these files in all installations. This requires a lot more effort though.

[alexcjohnson]

I suppose we could make the .map files optional (or not released at all, you need a full repo clone to get them) - those are really only useful for developers of dash itself. The dev bundle dash_renderer.dev.js is useful for dash app developers, so I wouldn't want to omit that. But we could minify it. Thanks for bringing this up!

[byronz]

@alexcjohnson @Marc-Andre-Rivet I think it might be a good candidate for 1.3.0, since we already have a better control on the assets with 1.2.0

[byronz]

#910 solved one part of this issue by removing completely the map files in the release process. now the compressed size is about half of the previous version.

Leave this issue open for dev bundle optimization in the future