Provide annotated saga mode

Why you need it?

Provide annotated saga mode:

• At present, SEATA has realized the orchestration Saga mode. The annotated saga can write business process directly through code. The cost of business process development is lower. Here is the pseudo code of annotation mode:

@SagaCompensatable(method="compensateOne", retryCount=3, retryIntervalSeconds=1.5, retryBackoffRate=1.5)
public Map<String, Object> one(String id, BeanA beanA){
    return null;
}

public boolean compensateOne(Context context){
    return true;
}

@SagaTransactional(compensateBy=CompensationException.class, lazyStart=true)
public Map<String, Object> processA(String id, BeanA beanA){
    Map<String, Object> oneResult = one(id, beanA);
    if("SUCCESS".equals(oneResult.get("RETURN_CODE"))){
        Map<String, Object> twoResult = two(id, beanA);
        return twoResult;
    }
    else{
        throw new CompensationException("ERROR_CODE", args);
    }
}