Move static code from visualizations and charts plugins into package

[flash1293]

There are a few shared helpers exposed by the visualizations and charts plugins. These should be moved into a package so they don't bloat the bundle size unnecessarily.

[elasticmachine]

Pinging @elastic/kibana-vis-editors @elastic/kibana-vis-editors-external (Team:VisEditors)

[stratoula]

@flash1293 which exactly helpers do you have in mind here?

[Kuznietsov]

@flash1293, WDTY about moving these files from charts plugin to @kbn/coloring? Please, mark those you approve:

• src/plugins/charts/common/static
• src/plugins/charts/public/static/colors
• src/plugins/charts/public/static/components
• src/plugins/charts/public/services/palettes/lighten_color.ts

[flash1293]

Good question both @stratoula and @Kunzetsov , should have clarified that. The stuff from charts sounds good, I went through visualizations but unfortunately a lot of that depends on types from app services plugins, so it's hard to move right now. Let's start with the charts stuff for now.

[Kuznietsov]

@flash1293, about visualizations plugin, I couldn't find anything to be extracted out to the package. Could you, please, specify, which exactly helpers you want to move out? Thanks.

[flash1293]

@Kunzetsov I wanted to move the "static code" block of exports:

kibana/src/plugins/visualizations/public/index.ts

Lines 19 to 22 in f576b1f

	export { TypesService } from './vis_types/types_service';
	export { VISUALIZE_EMBEDDABLE_TYPE, VIS_EVENT_TO_TRIGGER } from './embeddable';
	export { VisualizationContainer } from './components';
	export { getVisSchemas } from './vis_schemas';

But it doesn't work yet because they depend on the data plugin. So we will need for that to be sorted out first.

[stratoula]

Nice! Thanx you both, the above things sound as a good start for this charts oriented package!

[VladLasitsa]

Blocked due package structure not ready yet.

[markov00]

We should move MULTI_FIELD_KEY_SEPARATOR and MULTI_FIELD_VALUES_SEPARATOR into a package from their current position: data-common plugin.
This is because the same constant duplicates in multiple place and needs to be accessed both from packages and from plugins.