Update: 08.08.2019

I am happy with the current approach. But,

I want to set the class name of the topbar items so that I can still get control of control after build.
I believe using os.path.relpath when creating ics url is a must. The current approach use os.path.basename, although for me currently it doesn't cause problem but it would give users surprise if they put them in a subdirectory like <html-folder>/ics/events.ics.

Original Request

I understand it would be more reasonable to have exportCalendar be a boolean.
However, I use the html file as the home page so the corresponding output .ics would have an awkward file name index.ics in such case...
So, I want to add a backdoor with which I can give the *.ics another name whenever the exportCalendar variable is a string.
I would like to add an minimal working example of subscribing the calendar on the default html output, side-by-side with the Calendar export.
Otherwise, I am afraid that average users don't know how to make use of this functionality.
This part is a bit hard coded because on the one hand I would prefer to incorporate it with a proper CSS style file and have a nice-looking button, but on the other hand, it should stay working without.
- (LEFT) when use together with the given css file (can be access and included using http://ttreshad.web.cern.ch/ttreshad/meetings/style/style.css)
- (RIGHT) when use without (the default)
  The implementation is exactly the same, and the only difference is the former one uses the style file, which can be done with the
```
indicomb(*,
prebodyHTML=""" <head>
<link rel="stylesheet" type="text/css" href="http://ttreshad.web.cern.ch/ttreshad/meetings/style/style.css">
</head>"""
)
```

Edited Aug 08, 2019 by Yu-Heng Chen