Improve the calendar

[rolandgeider]

At the moment the calendar page is not really that useful, as it only shows the logs and sessions that are already in the system. It would be usefult if the calendar would show e.g. the next (planned) workout days and the logs or the gym mode could be started directly from there. Also, the calender is ugly.

Another idea, add a year view, similar to what github does with the contributions

[dometto]

Some suggestions for improvement on the calendar page:

• Make the current day 'active' by default, i.e. display any logs for today
• I like that you can edit a log directly from the calendar page, but it would be nice if this didn't refresh the page -- currently when I delete one exercise from a log, this resets the view and 'deselects' the day I was viewing.
• Why not also add an option to add an entry to a log, rather than just editing and deleting them?

These ideas seem pretty simple, so if they are desired, I'd be happy to have a go at implementing them.