Bug 31014: Minor UI problems in QOTD editor tool

Bug 31014: Minor UI problems in QOTD editor tool

This patch makes some cosmetic and functional updates to Quote of the
Day template, including simplifying some JavaScript, adding consisten
styles to buttons and page sections, and adding visible buttons to
jEditable text inputs.

The patch also improves the Quotes page breadcrumbs to add context
on the single quote entry page.

The patch removes quotes.css which is obsolete.

To test, apply the page and go to Tools -> Quote editor.

- The breadcrumbs should read "Tools -> Quote editor."
- Click the "New quote" button. The breadcrumbs should read "Tools ->
  Quote editor -> Add quote"
- Go back and click the "Import quotes" button.
- Confirm that the layout of the page looks good and that the upload
  instructions are shown.
- Upload a CSV file of quotes
  - The instructions should now show information about editing and
    saving quotes.
  - The "Save quotes" button should be styled consistently with other
    submit buttons.
  - Confirm that you can click in the "Source" and "Quote" table cells
    to trigger the display of a textarea where you can edit the text.
    Confirm that both the "Save" and "Cancel" buttons work.
  - Click the "Save quotes" button. A message should appear which shows
    how many quotes were imported.*
  - Confirm that your quotes are saved correctly, including any changes
    you made.

* This process could be improved: When the quotes are done importing the
toolbar doesn't change, and there isn't an indication that the import is
complete.

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>