[feature/1630] Add QR code button on signed transaction screen

[ThauanAmorim]

Task: #1630

New version:

ChangeLog:

• Added “Show Transaction as QR” button on signed transaction screen

[craigraw]

There are several issues here:

• The type of QR code shown is always BBQr (as opposed to UR). What device/app is reading this?
• Two default buttons onscreen
• The order of buttons (from left to right) differs from the previous signing screen. There, showing the QR code is on the left. Here is it on the right, where probably it should be in the middle.

[ThauanAmorim]

@craigraw
New version:

About "The type of QR code shown is always BBQr (as opposed to UR). What device/app is reading this?":

The QR code that appears is exactly the same as the one that appears in “file -> Show Transaction as QR”

So I don't think it's broken.

[craigraw]

Please motivate for this in the original issue.

[ThauanAmorim]

@craigraw Done!

[craigraw]

A few changes requested. Please squash to one commit.

[craigraw]

Thanks :)