Filter activities without category.

[tranko1]

Hello all,

I have a new map of a future travel to Japan, and I tried to not forget to setup a category for all the points.
Sometimes I missed it, so it could be nice to have the option int he dropdown to select "uncategorised" items, if you have missed ones to setup the category in the creation.

Regards,
Tranko.

[mauriceboe]

Implemented in dev — will be included in the next release. PR: #672