Conflicts:
	src/knot/dnssec/nsec-chain.c
	src/knot/dnssec/nsec3-chain.c
	src/knot/nameserver/name-server.c
	src/knot/nameserver/nsec_proofs.c
	src/knot/updates/ddns.c
	src/knot/updates/xfr-in.c
	src/knot/zone/node.c
	src/knot/zone/zone-diff.c
	src/knot/zone/zone-dump.c
	src/knot/zone/zone-load.c
	src/knot/zone/zone-load.h

- New removal of obsolete RRSIGs
- Adding RRSIGs with RRSet to changeset
- Signature shallow copy rewritten
- Bad assumptions about RRSet count in node rewritten

- Not complete: Empty non-terminal's RRSIGs are deleted, but NSEC3 are created. (already fixed in 'master' branch, will fix during merge)
- Fails nsec->nsec3 transition test

- TTLs might get mixed up if we added RRSIG just as any other record

Utils Edns

fixes #211

Conflicts:
	src/knot/server/zones.c

Zonefile loading fixes

Most is said in the commit.
I would have refactored zone-load more (especially the custom rrset lists could be standard ptrnode_t list from list.h) and a few other things,
also it should be named something like `zonefile.h` as we already have a `zone-load.h` file which is for zone loading in general and makes it confusing.
But I didnt, as @jkadlec made a lot of changes in the rrset->rrsigs and I suspect this would result in nasty collisions (like the rrset lists code).
So... this should be done after his branch is merge-able.

NSEC/NSEC3: Fixed wildcard expansion proofs and previous node lookup + tests

Most of it is written in the commit comments, it's still not pretty but at least it works for now.

- refactored the zone-loader a bit, as reading from zone file
  creates only contents and the zone is created separately
- refactored zone contents creating function, as it is always used in a
  way where an apex node is created and inserted into contents
- crash occured because created zone bound configuration and if parsing
  failed, the configuration was freed with the zone and also with the
  caller