Replacing string prototype id data fields with the new ProtoId<T> and EntProtoId types

[DrSmugleaf]

Data fields that store prototype ids can now use the EntProtoId and ProtoId<T> types to be validated without needing to specify a custom type serializer manually.
EntProtoId is a shorthand for ProtoId<EntityPrototype>.
There are also new PrototypeManager .Index, .HasIndex and .TryIndex methods that handle these new types.
This:

[DataField("preset", customTypeSerializer: typeof(PrototypeIdSerializer<StorePresetPrototype>))]
public string Preset = "StorePresetUplink";

[DataField("toggleAction", customTypeSerializer: typeof(PrototypeIdSerializer<EntityPrototype>))]
public string ToggleAction = "ActionToggleNinjaGloves";

Becomes:

[DataField]
public ProtoId<StorePresetPrototype> Preset = "StorePresetUplink";

[DataField]
public EntProtoId ToggleAction = "ActionToggleNinjaGloves";

New PRs must use these two new types where relevant.