- Added check for "empty" filename in loading of image.

Signed-off-by: Jan Nemecek <Nemecek.Jan@seznam.cz>
- Removed possibility to get ofstream member from CLog, since we don't want user to have direct access to file stream. Changed code that was using it to use stringstream member instead.

Signed-off-by: Jan Nemecek <Nemecek.Jan@seznam.cz>