build+ci: switch to python3

Also in this commit:
 * Sync CI scripts with other projects
 * Upgrade waf to version 2.0.19
 * Modernize docs/conf.py
 * Improve README.md and INSTALL.rst

Refs: #5095
Change-Id: Ic0f4f3be07d7266e57d6565a665eb24a757291e8
diff --git a/README.md b/README.md
index 603f016..60f1b1f 100644
--- a/README.md
+++ b/README.md
@@ -1,10 +1,33 @@
 # NDNS: Domain Name Service for Named Data Networking
 
+![Language](https://img.shields.io/badge/C%2B%2B-14-blue.svg)
 [![Build Status](https://travis-ci.org/named-data/ndns.svg?branch=master)](https://travis-ci.org/named-data/ndns)
 
-NDNS is a completely distributed database system that largely mimics the structure of the
-DNS system in today's Internet but operates within the NDN architecture.  Although the
-design of NDNS was primarily driven with a desire to provide support for cryptographic key
+**NDNS** is a completely distributed database system that largely mimics the structure of
+the DNS system in today's Internet but operates within the NDN architecture. Although the
+design of NDNS was primarily driven by the desire to provide support for cryptographic key
 distribution and routing scalability management, we believe that NDNS can also serve a
 number of other purposes during the development and deployment of the NDN architecture in
 coming years.
+
+## Installation
+
+See [`docs/INSTALL.rst`](docs/INSTALL.rst) for build instructions.
+
+## Reporting bugs
+
+Please submit any bug reports or feature requests to the
+[NDNS issue tracker](https://redmine.named-data.net/projects/ndns/issues).
+
+## Contributing
+
+We greatly appreciate contributions to the NDNS code base, provided that they are
+licensed under the GPL 3.0+ or a compatible license (see below).
+If you are new to the NDN software community, please read the
+[Contributor's Guide](https://github.com/named-data/.github/blob/master/CONTRIBUTING.md)
+to get started.
+
+## License
+
+NDNS is an open source project licensed under the GPL version 3.
+See [`COPYING.md`](COPYING.md) for more information.