Remove the unnecessary empty string argument

rubberin

@@ -163,7 +163,7 @@ end
 # do an initial run.
 files = `rubber-info --deps #{infile}`.chomp.split
 compile(infile, mode)
-puts ""
+puts
 
 # Spawn a viewer based on the mode.
 viewer_pid = fork
@@ -198,7 +198,7 @@ dirs.each do |dir|
     puts "I: file #{ev.name} modified, compiling #{infile}..."
     compile(infile, mode)
     reload(infile, mode)
-    puts ""
+    puts
   end
 end