Protocol for encoding Elixir terms to TOML.

You can derive this protocol for structs:

@derive TomlElixir.Encoder
defstruct [:name, :age]

@derive {TomlElixir.Encoder, only: [:name]}
defstruct [:name, :age, :password]

@derive {TomlElixir.Encoder, except: [:password]}
defstruct [:name, :age, :password]

If you don't own the struct, you can derive externally:

Protocol.derive(TomlElixir.Encoder, NameOfTheStruct, only: [:field])
Protocol.derive(TomlElixir.Encoder, NameOfTheStruct, except: [:field])
Protocol.derive(TomlElixir.Encoder, NameOfTheStruct)