Fix: tests: Make blackbox_segfault.sh not depend on bash
Fix: tests: On some platforms -ECONNRESET is returned rather than -ENOTCONN after server failure
Fix: ringbuffer: Add file header version field and detect reading corrupted blackbox files using hash value

In the future, if something changes in the file header we can
increment the version and split up the parsing into separate functions
for backwards compatibility.
Fix: refcount leak
Low: tests: Verify reading valid blackbox file works