Move buttons and links in 'progresses#_progress' to partial template

app/views/progresses/_buttons_and_links_in_td.html.erb
- Newly created, taking over the buttons and the links for
  Progress from view 'progresses#_progress'.
app/views/progresses/_progress.html.erb
- Move the buttons and the links for Progress to a new
  partial template.
Add buttons and links to manipulate Progress in 'progresses#index'

app/helpers/application_helper.rb
- Add link_to_browse_back().
app/views/progresses/edit.html.erb
- Correct to use helper link_to_browse_back() for the link
  to go back.
app/views/progresses/index.html.erb
- Add buttons and links to manipulate each Progress.