Canceled Events: add CSS class

[felixhahnweilheim]

This PR adds a CSS class 'canceled' to canceled events. This way themes can manipulate the background color of the event or strike through the title.

Related: #320

Please let me know if I also should add CSS to strike through the title.

[felixhahnweilheim]

This CSS would work for month, week, day and list view and only strike through the event title, not the time.

.fc-view .canceled .fc-title, .fc-view .canceled .fc-list-item-title {
  text-decoration: line-through;
}

[luke-]

@felixhahnweilheim Thanks for the PR.

Can you please add a screenshot with the strikethrou? Then we can discuss whether to add it.

[felixhahnweilheim]

[luke-]

@Eladnarlea What do you think?

[Eladnarlea]

@luke- I like the idea and think it is useful information. Do we need the extra (canceled) info even if the title has already been struck through?

@felixhahnweilheim do you suggest to leave the time as it is, or is it not possible to strike it through as well?

this is how it looks in apple calendar.

[felixhahnweilheim]

I have updated the PR to the following:

[luke-]

@felixhahnweilheim @Eladnarlea Thank you!