Sync build system and CI scripts with ndn-cxx

 * Update build flags
 * Update waf to version 2.0.21
 * Replace Travis CI with GitHub Actions

Change-Id: Ic9331d1d86681e6a4dfbfa6e8286cbba50852dfd
diff --git a/.gitignore b/.gitignore
index 608c272..8850587 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,4 +26,4 @@
 *.py[cod]
 
 # Other
-/VERSION
+/VERSION.info