feat: support eureka registry (#464)

Signed-off-by: charlie <qianglin98@qq.com>

registry/eureka/client/struct.go

@@ -0,0 +1,23 @@
+// Copyright (c) 2022 Alibaba Group Holding Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package client
+
+import "github.com/hudl/fargo"
+
+type Applications struct {
+	Apps         map[string]*fargo.Application
+	HashCode     string
+	VersionDelta int
+}