fa user and post controller cleanup

Rakefile

@@ -77,16 +77,18 @@ end
 namespace :db_sampler do
   task :export => :environment do
     url_names = ENV["url_names"] || raise("need 'url_names' (comma-separated)")
-    outfile_path = ENV["outfile"] || raise("need 'outfile' (file path)")
-    outfile = File.open(outfile_path, "wb")
+    # outfile_path = ENV["outfile"] || raise("need 'outfile' (file path)")
+    # outfile = File.open(outfile_path, "wb")
+    outfile = $stdout
     DbSampler.new(outfile).export(url_names.split(","))
   ensure
     outfile.close if outfile
   end
 
   task :import => [:environment] do
-    infile_path = ENV["infile"] || raise("need 'infile' (file path)")
-    infile = File.open(infile_path, "rb")
+    # infile_path = ENV["infile"] || raise("need 'infile' (file path)")
+    # infile = File.open(infile_path, "rb")
+    infile = $stdin
     DbSampler.new(infile).import
   ensure
     infile.close if infile