Improvements to profilepic

Description

Ok, as you clarified in #14 (closed), you don't have the ability to get the profilepics. Still, I think it would be better if you copied what Signal does for profiles that has no picture. That is:

1. Using a flat color. That's the hip new thing all the cool kinds does nowadays.
2. Using the first letter in the first and last name in the colored circle instead of a generic head. Your profile circles are quite small, so you might select to just use the first letter of the first name instead of both.
3. Using a darker version of the background color for the color of the letters.

Thanks! :)