Pretty formatting default values into multiple lines?

[LukasKalbertodt]

Right now all default values are printed in the config template in one line, e.g. # Default value: { foo: 3, bar: 4 } inline-map syntax. If the default values are complex, that's not very pretty to read. Instead it would be nice to have those into multiple lines, e.g.

# Default value:
#   foo: 3
#   bar: 4

Thats a bit tricky to implement, but there are also open questions: when to use one line and when to use multiple ones? Should library users be able to have control over that? Maybe give users even more control over how each default value is formatted? And how to exactly print: see example above, this maybe looks weird?