fix: ostream::write will not be called if length of message text is equal to zero.
     istream::read and allocation of memory for text-buffer will not be called, if text-length is equal to zero.
fix: incorrect business-logic
fix: correct output format in task 2.6
Merge pull request #162 from PeterMoroz/puzzles-2-review

Puzzles 2 review from Peter Moroz