The problem with previous code was that the packet stripped the TSIG
section when it parsed the first IXFR packet from wire. If the code
failed though, the wire was parsed again but this time the TSIG was
already stripped on the wire so the result was garbled data.
I've thrown in some minor cleanup as well.

Zone Create No Lastnode

This makes NSEC3 nodes disappear if it is preceded by a RR with the
same owner and any other record type.

Explained in the test, BIND9 as of 9.9.4 provides wrong closest
encloser wildcard NSEC3 record.

Fix Ddns

Fixes for new tests, tests were modified a bit as well.

Improve Ddns Tests

- Every scenario from old tests rewritten, plus some new ones added, some are still failing

Rrset Free Remove

I'm not sure if this will conflict with some of your work, if yes. we'll cancel this.

- nodes were marked as empty, but the information was never used ...
- renamed one function for clarity.

Fixes #218

Log Control

refs #222

DDNS tests for new test suite

Include config.h

The config.h is now implicitly included using -include option of the
compiler. After this change, config.h need not be placed at the first
position in all source files.

Conflicts:
	src/knot/server/xfr-handler.c

Conf Optimization