feat: Calendar Events implemented.

[develoopeer]

• Ics files widely used format to represent calendar info parsed via https://github.com/arran4/golang-ical library. It is super lightweight and can parse ics files from different sources. Google calendar, Trello and local files were tested by me.

• Events in calendar will be highlighted with color-primary color, and have hover text.

• If you have more than 1 event at the same day for one day, only first one will be displayed.
  Complete version looks like this:
  

• Icsurl option added to yaml configuration

- type: calendar
  icsurl: https://testsite/validurl.ics

For example to grab url from google calendar you need to make your calendar public, click on calendar settings and get url from ics field. Instruction. Same goes for Trello

• Events will be updated every hour, because of default Calendar Widget Initialize function declared with withCacheOnTheHour() function. This time can be increased or decreased, but i don`t think it is necessary.
• I feel like icsurl option can be replaced with icsurls option, to allow you gather events from different sources. This behavior can be simply implemented, but i don`t know is it really useful. I need your opinion for that.

[develoopeer]

Hello @svilenmarkov. Will this PR be merged in the near future?

[svilenmarkov]

@develoopeer Hey, yeah sorry, calendar events were planned for v0.7.0 so I'll get it merged before that comes out, just wanted to make a couple of changes that I haven't had the chance to work on yet.

[develoopeer]

Ooh i got it. I will resolve emerging conflicts in this PR in near future. Hope v0.7.0 will be coming out soon.

[Anachron]

Can we make displaying all events optional?

I dont know how useful it will be to show the first event, when I have a ton of events every day.

Also how trivial is adding caldav support? (As in I set up my login details and it pulls all events from a collection)

Thanks for the work so far! :)

[develoopeer]

Hello @Anachron. Thanks for mentioning caldav support. I briefly tried to implement some caldav support, and was able to make it without any custom libraries. i will say that caldav integration will not be that hard. And about your questions:

• Yes, events can be cut to show only last one or first one, i will add a specific option for that
• I will try to add support to caldav soon. To integrate your custom caldav server to glance, you will need to provide login, password, calendar name. All that options will be available.

[Anachron]

That's a better answer than I expected. Thank you and take care! 👍