bin/wrongdoc in wrongdoc-1.5.0 vs bin/wrongdoc in wrongdoc-1.6.0

@@ -1,7 +1,8 @@
 #!/usr/bin/env ruby
-usage = "Usage: #{File.basename($0)} [prepare]"
+tasks = %w(prepare release_notes release_changes all)
+usage = "Usage: #{File.basename($0)} [#{tasks.join('|')}]"
 $stderr.sync = $stdout.sync = true
 require 'wrongdoc'
 opts = Wrongdoc.config
 case ARGV[0]
 when "prepare"
@@ -14,7 +15,8 @@
   Wrongdoc::Prepare.new(opts).run
   Wrongdoc::Rdoc.new(opts).run
   Wrongdoc::Merge.new(opts).run
   Wrongdoc::Final.new(opts, ARGV[1]).run
 else
-  abort "#{$0.inspect} #{ARGV.inspect} not understood"
+  warn "#{$0.inspect} #{ARGV.inspect} not understood"
+  abort usage
 end