nextgen in nextgen-0.16.0

- old
+ new

@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
 
 require "nextgen"
 
 # Work around an "unresolved or ambiguous specs" warning when CLI is run via `gem exec`
 # https://github.com/rubygems/rubygems/issues/6914