Internationalization of QTads interface

[tseykovets]

There are many TADS games written in different languages, not just English.
QTads supports setting the encoding for the TADS 2 virtual machine so that it can run games in different languages.
However, QTads does not support internationalization of the interface so that the program can be conveniently used by people speaking different languages.

I suggest considering adding support for internationalization of the QTads interface.
For example, the gettext system can be used for this: connect the system, wrap all interface lines in the gettext function and provide the ability to add translations.
It is also useful to add to the preferences the ability to explicitly select the interface language.

If this feature were implemented, it would expand the audience of QTads and make it useful to more fans of interactive fiction.