New event from the global calendar: display "Select space..." instead of first Space

[marc-farre]

When the Calendar module is enabled in the user account, it's fine:

But when it's disabled, the first Space is chosen by default.

Users often think it's the best place to create the event, because it's the default one.

But in fact, the first Space is the last visited one.

So when the Calendar module is disabled in the user account, it would be better to prompt "Select space..." to force them choosing the right space:

Related to #223

@luke- if you agree, I can send a PR.

[luke-]

@marc-farre Yes please!

[marc-farre]

@luke- PR #527

Requires new translations.

[luke-]

Thanks for the info. As soon as the PR is merged, I'll update the translation site.