build: recommend boost >= 1.65.1

With this commit, Ubuntu 16.04 is no longer officially supported
and may require manual installation of a newer version of Boost.

Refs: #5087
Change-Id: I17197f72ee8f7cd4d0954658fe57c324076f1311
diff --git a/tests/unit/main.cpp b/tests/unit/main.cpp
index cb54695..51edc79 100644
--- a/tests/unit/main.cpp
+++ b/tests/unit/main.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2013-2018 Regents of the University of California.
+ * Copyright (c) 2013-2020 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -20,91 +20,4 @@
  */
 
 #define BOOST_TEST_MODULE ndn-cxx Unit Tests
-
-#include <boost/version.hpp>
-
-#if BOOST_VERSION >= 106200
-// Boost.Test v3.3 (Boost 1.62) natively supports multi-logger output
 #include "tests/boost-test.hpp"
-#else
-#define BOOST_TEST_ALTERNATIVE_INIT_API
-#define BOOST_TEST_NO_MAIN
-#include "tests/boost-test.hpp"
-#include "tests/unit/boost-multi-log-formatter.hpp"
-
-#include <boost/program_options/options_description.hpp>
-#include <boost/program_options/variables_map.hpp>
-#include <boost/program_options/parsers.hpp>
-
-#include <fstream>
-#include <iostream>
-
-static bool
-init_tests()
-{
-  init_unit_test();
-
-  namespace po = boost::program_options;
-  namespace ut = boost::unit_test;
-
-  po::options_description extraOptions;
-  std::string logger;
-  std::string outputFile = "-";
-  extraOptions.add_options()
-    ("log_format2", po::value<std::string>(&logger), "Type of second log formatter: HRF or XML")
-    ("log_sink2", po::value<std::string>(&outputFile)->default_value(outputFile), "Second log sink, - for stdout")
-    ;
-  po::variables_map vm;
-  try {
-    po::store(po::command_line_parser(ut::framework::master_test_suite().argc,
-                                      ut::framework::master_test_suite().argv)
-                .options(extraOptions)
-                .run(),
-              vm);
-    po::notify(vm);
-  }
-  catch (const std::exception& e) {
-    std::cerr << "ERROR: " << e.what() << "\n"
-              << extraOptions << std::endl;
-    return false;
-  }
-
-  if (vm.count("log_format2") == 0) {
-    // second logger is not configured
-    return true;
-  }
-
-  std::shared_ptr<ut::unit_test_log_formatter> formatter;
-  if (logger == "XML") {
-    formatter = std::make_shared<ut::output::xml_log_formatter>();
-  }
-  else if (logger == "HRF") {
-    formatter = std::make_shared<ut::output::compiler_log_formatter>();
-  }
-  else {
-    std::cerr << "ERROR: only HRF or XML log formatter can be specified" << std::endl;
-    return false;
-  }
-
-  std::shared_ptr<std::ostream> output;
-  if (outputFile == "-") {
-    output = std::shared_ptr<std::ostream>(&std::cout, std::bind([]{}));
-  }
-  else {
-    output = std::make_shared<std::ofstream>(outputFile.c_str());
-  }
-
-  auto multiFormatter = new ut::output::multi_log_formatter;
-  multiFormatter->add(formatter, output);
-  ut::unit_test_log.set_formatter(multiFormatter);
-
-  return true;
-}
-
-int
-main(int argc, char* argv[])
-{
-  return ::boost::unit_test::unit_test_main(&init_tests, argc, argv);
-}
-
-#endif // BOOST_VERSION >= 106200