Profile certificates

Includes:

• profile certificate generation and server sign.
• storing the profile certificates in the local crypto storage.
• one-time profile certificate generation.

cpp/tests/integration/integration_test.cc

@@ -85,8 +85,8 @@ TEST_CASE("C API integration", "[.integration]") {
 
   // std::cout << vereign::test::ProtobufToJson(getDIDsResp) << std::endl;
 
-  grpc_shutdown();
-  google::protobuf::ShutdownProtobufLibrary();
+  // grpc_shutdown();
+  // google::protobuf::ShutdownProtobufLibrary();
 }
 
 TEST_CASE("vereign_service_start") {