Add first draft for TE service

proto/te.proto

+syntax = "proto3";
+package te;
+
+import "context.proto";
+import "service.proto";
+
+service TEService {
+  rpc RequestLSP(service.Service  ) returns (service.ServiceState) {}
+  rpc UpdateLSP (service.ServiceId) returns (service.ServiceState) {}
+  rpc DeleteLSP (service.ServiceId) returns (context.Empty       ) {}
+}