[template] Include a pointer to incubation practices, location

[wseltzer]

See also https://github.com/w3c/wg-effectiveness/blob/master/continuous_incubation.md

[wseltzer]

Charters might want to indicate where related incubation happens (in WG, CG, WICG, etc.)

[nigelmegitt]

Also scope of incubation, how incubation contributions can be made, and if different IPR requirements for such contributions (e.g. to allow CG-style "incubation membership" of a WG) apply.

[svgeesus]

related:

• CSSWG, WICG liaison
• CSSWG, module splitting / merging and incubation provision
• svgcg-2019, Defining incubation
• WebApps charter: Implementor interest

[svgeesus]

This seems to depend on add an Incubation explainer. The charter template can then point to that, which solves part of the issue.

The remaining part (where incubation happens, for a given WG) also relates to Add to charter template hook for CG relationship (split of work, etc.)