* Make `YamlLoader` generic on the type of the `Node`. This is required
because deeper node need to have annotations too.
* Add a `LoadableYamlNode` trait, required for YAML node types to be
loaded by `YamlLoader`. It contains methods required by `YamlLoader`
during loading.
* Implement `LoadableYamlNode` for `Yaml`.
* Take `load_from_str` out of `YamlLoader` for parsing non-annotated
nodes. This avoids every user to specify the generics in
`YamlLoader::<Yaml>::load_from_str`.
This implements the IndexMut trait for Yaml. This allows indexing the
Yaml type while having a mutable reference.
Unlike the Index, this will panic on a failure. That is allowed as per
the Rust documentation [1]. We don't have the option of returning a
mutable reference to BAD_VALUE as that is unsafe. So instead we just
panic.
1: https://doc.rust-lang.org/std/ops/trait.IndexMut.html#tymethod.index_mut
Resolves: https://github.com/chyh1990/yaml-rust/issues/123
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Co-authored-by: Ethiraric <ethiraric@gmail.com>
