build: Upgrade waf to version 2.0.6

This commit also includes:
- cleanup of build scripts
- replacing log4cxx with ndn-cxx logging facility

Change-Id: I96fd673a3cd2e06061e9efc1a7891e41cf97ea4f
diff --git a/.gitignore b/.gitignore
index 00e73a3..608c272 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,29 @@
-.DS*
-.waf-1*
-.waf3-*
-.lock*
-**/*.pyc
-build/
-VERSION
-unit-tests.log4cxx
+# Emacs
+*~
+\#*\#
+/.emacs.desktop
+/.emacs.desktop.lock
+*.elc
+.\#*
+
+# Visual Studio Code
+.vscode/
+
+# macOS
+.DS_Store
+.AppleDouble
+.LSOverride
+._*
+
+# Waf build system
+/build/
+.waf-*-*/
+.waf3-*-*/
+.lock-waf*
+
+# Compiled python code
+__pycache__/
+*.py[cod]
+
+# Other
+/VERSION