build: align minimum build dependencies with ndn-cxx

* gcc 7.4
 * clang 6.0
 * Xcode 10.0 (11.3 or later recommended)

Change-Id: I365e7b1e2c9b081e512f511bf5beee2487cfc361

docs/RELEASE-NOTES.rst

@@ -1,4 +0,0 @@
-Release Notes
-=============
-
-.. include:: release-notes-latest.rst

docs/conf.py

@@ -18,7 +18,7 @@ import sys
 # -- Project information -----------------------------------------------------
 
 project = u'PSync: Full/Partial Synchronization Protocol for NDN'
-copyright = u'Copyright © 2018-2021 Named Data Networking Project.'
+copyright = u'Copyright © 2018-2022 Named Data Networking Project.'
 author = u'Named Data Networking Project'
 
 # The short X.Y version.

docs/index.rst

@@ -32,10 +32,10 @@ PSync Documentation
 
    install
    examples
-   RELEASE-NOTES
+   release-notes
    releases
 
 -  :doc:`install`
 -  :doc:`examples`
--  :doc:`RELEASE-NOTES`
+-  :doc:`release-notes`
 -  :doc:`releases`

docs/release-notes-latest.rst

@@ -1 +0,0 @@
-release-notes/release-notes-0.3.0.rst

docs/release-notes.rst

@@ -0,0 +1,4 @@
+Release Notes
+=============
+
+.. include:: release-notes/release-notes-0.3.0.rst