Enable users to use the tag system in galery - idea for enhancement

[elpraga]

Currently it is not possible to assign or use tags from the gallery app, which is unfortunate, because it would be a great way to effectively sort through larger galleries. The tag system in the files app is not very useful for photos, as the thumbnails shown is very small and hard to see and in the files app is impossible to set more then one tag at a time now.

Being able to take advantage of the larger and better visible previews in the gallery app and being able to set a tag to several photos at once would be a huge improvement for photo viewing.

This issue might be connected to #17 , but I wasn't sure if it would be appropriate to include it, that is why I opened a new one.

[elpraga]

Duplicate of #153