[Qt] use tr() instead of QObject::tr() in intro.cpp
[Qt] remove unused optionsmodel from addressbookpage
Merge pull request #3205 from Diapolo/intro

[Qt] use tr() instead of QObject::tr() in intro.cpp
Merge pull request #3206 from Diapolo/addressbookpage_model

[Qt] remove unused optionsmodel from addressbookpage