[editor] Format the text on saved.

[lmcbout]

When editing in any editors, on saved, the data inside the file should be formatted. The text should be aligned.

[jankeromnes]

Great suggestion! Having an option to do this would be nice.

This could be used for example to run Prettier on Save (but since this is opinionated, I think it should be a configuration option).

[paulmelnikow]

Prettier is designed to be integrated into editors to format on save. It has many existing editor integrations.

Running it automatically on save would be a big help for Shields contributors (badges/shields#2783), and similarly for any other project using Prettier.