use implicit recursion similar to fromPartial for toAmino/fromAmino

currently the toAmino/fromAmino functionality requires the proto parser store and proto refs so that it can query information about nested dependencies and imports.

This could be simplified by taking an approach for amino encoding similar to how `fromPartial`, `fromJSON`, `toJSON` and other methods inspired from `ts-proto`

This could be accomplished by adding toAmino` and `fromAmino` methods to the message objects:

```js
export const MsgCreateValidator = {
encode(message: MsgCreateValidator, writer: _m0.Writer = _m0.Writer.create()): _m0.Writer {
if (message.description !== undefined) {
Description.encode(message.description, writer.uint32(10).fork()).ldelim();
}
if (message.commission !== undefined) {
CommissionRates.encode(message.commission, writer.uint32(18).fork()).ldelim();
}
}
toAmino(message, obj) {
if (message.description !== undefined) {
obj.description = Description.toAmino(message.description);
}
}
```