Add a share portal

[Aurnytoraink]

It would be interesting to have a portal that allow to share text, photos, musics, files between apps.

All apps should have a config file that includes what type of file they support, and the actions they do when they received the file.
For example, you have a picture, so you can publish it on Twitter or send it to your friend.

Also, you can directly bind contact or devices (e.g., via Bluetooth)

Here is a visual
PS: I'm not a professional designer

[jadahl]

See #12.

[Aurnytoraink]

It seems I don't know how to use search engine 💀

[jadahl]

Closing since #12 already covers this.
/close