Update proto files and scripts

bg/api/common.proto

@@ -0,0 +1,15 @@
+syntax = "proto3";
+
+package bg.api;
+
+option go_package = "bg/api/protobuf/common";
+option java_package = "bg.protobuf";
+option java_outer_classname = "CommonProto";
+option java_multiple_files = true;
+
+enum MessageType {
+    RECORD = 0; // 通用数据记录
+    TRANSACTION = 1; // 交易
+    CONTRACT_CREATION = 2; // 合约创建
+    CONTRACT_INVOCATION = 3; // 合约调用
+}