问题： Incompatible fallback instance. Fallback/fallbackFactory of type
class com.spring.cloud.hystrix.MyFallbackFactory is not assignable to
interface com.spring.cloud.api.EmployeeService for feign client
test-provider
译文：不兼容的fallback实例。myfallbackfactory类型的Fallback/fallbackFactory不能分配给接口，
大概意思就是
@FeignClient注解中，fallbackFactoty属性和fallback属性要分清，不要搞混。之前我写的fallback，后面类是实现的FallbackFactory.
@FeignClient(value ="test-provider",fallbackFactory=MyFallbackFactory.class)
