Updating to toml 0.8

I am currently looking at updating the toml crate in Debian to 0.8, the upstream changelog has the following to say.

Serialization and deserialization of tuple variants has changed from being an array to being a table with the key being the variant name and the value being the array

The tests pass succesfully with the new version, but I'd still appreciate feedback from those more familiar with the codebase as to whether this is likely to cause any issues for debcargo.