With this patch we move the codebase to Rust-2018.
The diff was generated by executing
cargo fix --all --all-features --edition
on the codebase.
Signed-off-by: Matthias Beyer <mail@beyermatthias.de>
Before we extracted the store configuration from the configuration
toml::Value object and passed it to the store.
This is unecessary overhead.
Now we pass the whole configuration object and let the store extract the
required values.
