Rendering issue on small screens (PinePhone)

[tfardet]

On mobile device screens, the 0.2.4 release has some rendering issues associated to the small terminal width:

• QR code does not fit terminal width (each real line is rendered over two lines)
• sender line (date + contact name) is too long and compresses message to one or few words per line

Potential solutions:

1. detect terminal width in char numbers and adapt QR code or use PNG in that case
2. put message time and contact name on two lines
3. compute contact name length and only use initials
4. mark date only once on a separate (centered?) line and mark only time on the message line
5. use a combination of 2, 3, and 4

Illustration of the issue

Current look:

[data] [time] [contact name]: This is
                              how the
                              message
                              looks

Proposed solution

                [date]

[time] [CN]: This is how the message
             could look.

[time] [me]: And this is an answer.

[boxdot]

Done in #164