Create a format_string_std function that works like format_string,
but does return a std::string instead of a strdup()ed C string.
Make it a global function to be used in other parts of the code.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
This was very annoying, because the old code was not const-clean
at all and trampled all over buffers. This makes the new code
pretty messy for now.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
