Form value handling for Arrays and Hashes

This processes Array and Hash values and converts those to strings that
can be appended to the spreadsheet

app/models/submission.rb

@@ -12,8 +12,15 @@ class Submission < ApplicationRecord
   end
 
   def submission_value(value)
-    if value.to_s.downcase == 'tinyforms_now'
+    case value
+    when Array
+      value.join(', ')
+    when Hash
+      JSON.dump(value)
+    when 'tinyforms_now'
       Time.now.utc.to_formatted_s(:rfc822)
+    when ActionDispatch::Http::UploadedFile
+      ''
     else
       value.to_s
     end