using our util::_Fmt front-end helps to reduce the code size,
since all usages rely on a single inclusion of boost::format
including boost::format via header can cause quite some code bloat
NOTE: partial solution, still some further includes to reorganise
there was the possibility for the random offset added in this test
to add up to a whole frame, which would cause the
re-quantisation to wrap to the next fame (and thus the
CHECK in line 110 to fail.
the buildsystem will now pick up and link
all test cases according to the layer, e.g.
backend tests will automatically be linked
against the backend + library solely.
