OutputFileMedium is designed to be a super-class for classes that need
to write to a text file. It could also be a simple writer if the method
write_string_to_file() was public (maybe we should change that and
rename OutputFileMedium to OutputFileWriter or something like that).
InputLogCSV:
- Now extends InputLogMedium *and* OutputFileMedium.
- Make log_request() inline.
- Where possible, use initialisation lists in class definition instead
of explicit variable initialisations in source file.
- Rename some variables (use of "source" in copy constructors and
operators…).
- Suppress useless Doxygen comments, allow non-documented members in
Doxyfile.