Invalid writes were detected by Valgrind and fixed.
Cleaning and freeing of Response, Request and Keyval structures
has been improved by adding *_free functions,
which frees blocks of memory after calling *_cleanup.
This helps avoid confusion when you want to completely clean memory,
and *_cleanup functions only _clean_ data without _freeing_ memory blocks.
_Cleaning_ to reuse already allocated memory blocks later,
but without data, is still available in *_cleanup functions.
Ivan Polyakov