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/README-dev.md b/README-dev.md
index ad9447c..95b7ee1 100644
--- a/README-dev.md
+++ b/README-dev.md
@@ -2,7 +2,7 @@
 ============================
 
 If you are new to the NDN community of software generally, read the
-[Contributor's Guide](https://github.com/named-data/NFD/blob/master/CONTRIBUTING.md).
+[Contributor's Guide](https://github.com/named-data/.github/blob/master/CONTRIBUTING.md).
 
 Code style
 ----------
@@ -62,7 +62,7 @@
 
     ./build/unit-tests
 
-[Boost.Test framework](https://www.boost.org/doc/libs/1_58_0/libs/test/doc/html/index.html)
+The [Boost.Test framework](https://www.boost.org/doc/libs/1_65_1/libs/test/doc/html/index.html)
 is very flexible and allows a number of run-time customization of what tests should be run.
 For example, it is possible to choose to run only a specific test suite, only a specific
 test case within a suite, or specific test cases within specific test suites:
@@ -94,9 +94,8 @@
     ./build/unit-tests -p
 
 There are many more command line options available, information about which can be obtained
-either from the command line using `--help` switch, or online on
-[Boost.Test library](https://www.boost.org/doc/libs/1_58_0/libs/test/doc/html/index.html)
-website.
+either from the command line using the `--help` switch, or online on the
+[Boost.Test website](https://www.boost.org/doc/libs/1_65_1/libs/test/doc/html/index.html).
 
 **Warning:** If you have customized parameters for NDN platform using `client.conf` in
 `/etc/ndn` or `/usr/local/etc/ndn` (or other `@SYSCONFDIR@/etc` if it was configured to custom