Full size profile picture

**Is your feature request related to a problem? Please describe.**
For now it is not possible to view your own profile picture in full size, like it is for your contacts. At least I didn't found one.

**Describe the solution you'd like**
Provide an option to view the own profile picture in full size.

**Describe alternatives you've considered**

* In the left side menu, by tapping on the profile icon
* In the settings by tapping on the icon, instead if the description
* In the settings after you have chosen your profile picture, before it is saved