Merge pull request #2960 from jsquyres/pr/v2.x/nightly-script-updates

v2.x: create_tarball: read $debug from environment

Author: jsquyres

contrib/nightly/create_tarball.sh

@@ -34,7 +34,7 @@ gitbranch=$5
 
 # Set this to any value for additional output; typically only when
 # debugging
-debug=1
+: ${debug:=}
 
 # do you want a success mail?
 want_success_mail=1