Option to turn off the shop (holidays, ...)

[mlocati]

What about adding a way to turn off the e-commerce?

I'd add these options:

• Disable e-commerce
  • from [date/time]
  • until [date/time]
• Rich text message to be displayed to site visitors

If:

1. "disable e-commerce" is turned on
2. and "from" is empty or a date/time in the past
3. and "to" is empty or a date/time in the future

Then the checkout would be disabled.
Also, in the /checkout and /cart pages we could display (if set) the configured rich text message.

This would be very helpful for example in case of holidays, as well as in any case when products can't be shipped for some days.

We could also add a new block type that doesn't output anything if the e-commerce is active, but displays the rich text message if the e-commerce is disabled (for example, we could add that block to the homepage, or in a global area so that it's displayed in every page).

If that's ok, I can of course submit a pull request with these features.

[mlocati]

What about #782?