Many calls to print warnings use the deprecated function which ignores verbosity

[markus-jehl]

Currently, most calls of warning() use the deprecated version of the function. This function turns out to ignore the verbosity. I would propose to replace all these calls to the deprecated version with boost::format formatted calls to the proper version.

E.g. https://github.com/UCL/STIR/blob/734a0d713df4318cea10f1a8ec5aea90ca093254/src/IO/InterfileHeader.cxx#L1397 would become: warning(boost::format("Interfile parsing ended up with the following scanner:\n%1%\n") % scanner_ptr_from_file->parameter_info().c_str());