FR: Show email count in the tags

[gerroon]

Hi

I personally think that being able to see the number of emails or rounded number of emails in the tag lines on the left could be very beneficial especially for things like TODO tags. So when you add a TODO tag to an email it would naturally increase the number of emails in the tag. if no emails exists in the tag then there would be no number.

This could make Mailpile to be more of a productivity tool as well.

thanks