* Added a couple of utility macros to help with the conversion. lit() is
paired with tr() for untranslated text.
* QFormatStr is more explicitly for non-textual formatting strings.
* Both are just #define'd to QStringLiteral()
* Apart from making the code cleaner when accessing them, creating these
from strings can be slow if you do it often enough (e.g. once per
resources for action/action_hover in pipeline state view).
baldurk