Creating nested form for add items

1. adding coccon gem
2. modify the list model
3.create form and item_fields partials
Merge branch 'testing-include-item-with-cocoon'
making the model understand the date passed by the forms
Merge branch 'fixing-datepicker-again'
Merge branch 'master' into fixing-datepicker-again
check the update datepicker later
Merge branch 'fixing-datepicker-again'
Merge branch 'master' of https://github.com/alicelara/luggish

Conflicts:
	config/routes.rb