refs #1087

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

- Renamed to either deep_copy or shallow_copy.
- Removed zonedb_copy() (not used).

Conflicts:
	src/knot/conf/cf-lex.l
	src/zcompile/zcompile.c
	src/zcompile/zparser.y

- Was not increasing reference count.

refs #993

+ changed RRSet comparing function to compare also TTLs

fixes #1030 @ 45m

* Node and rrset now must use new API for changing owner (*_set_owner())
* Every structure that stores pointer to dname must retain reference to it
* Destructors in rrset now release all stored dnames, obsoletes parameters: free_owner
* Destructor in rdata_deep_free has obsolete parameter: free_all_dnames
* Fixed some direct data manipulation
* Some code readability improvements
* To do:
 * Reference counting in zparser is disabled for now, implement correctly.
 * Remove obsolete parameters.
 * Destructors should have no extra parameters.
* Tested with server startup, querying and AXFR client/server

Commit refs #993.

Refs #1068 @3h

No leaks so far with server execution.

* Newly created dnames have refcount=1, caller is responsible for releasing them.
* Copied dnames have also refcount=1 (as they are new).

To do:
* Carefully implement more uses of dname not protected by refcounting.
* Consider renaming dnslib_dname_copy() do _duplicate() as it creates duplicate.
* Consider shallow copying of dname, as it's possible with refcounting.
* Test and review.

Commit refs #993.

GCC builtins are used for atomic add/sub and fetch.
May be extended with assembly for other compilers later.

Commit refs #993.

refs #643 @10m

- Fixed rehashing based on unittest output.
  TODO: there is still some condition on which it crashes on
        segfault; hard to replicate.
- Small fixes in zone, zone tests.

refs #643 @30m

refs #641 @1h30m

Added setting of previous node field. Removed assert that should not be there and was coushing abort with cz. zone (I removed that one before, too :D)
Closes #1069

- They were causing the compiler to crash.

- Zonedb always uses zone->name as the key.
- Removed assert from dnslib_node-parent(), replaced by check.
  (Probably should do the same with other such asserts there.)
- Reenabled adjust_rrsets() function (don't know why it was
  disabled).
- Fixed wrong assert in zone-contents

* Fixed XFR client termination
* Updated to new APIs

Conflicts:
	src/dnslib/zone.c
	src/knot/server/dthreads.c
	src/knot/server/xfr-handler.c
	src/knot/server/xfr-handler.h

- When the search in AVL tree went to the leftmost node, it did
  not return any 'previous' node. This was fixed in the AVL
  implementation by distinguishing this case. It may have impact
  on the performance as there is now one more condition jump
  for each encountered node during search. But it seems there is
  no better way around it.
- Fixed the usages of the tree-finding functions.

fixes #1065 @2h

Commit refs #1063.

- Setting zone pointer to NSEC3 nodes inserted into the zone.
- Fixed searching for NSEC3 node for some name
  (find_nsec3_for_name()) - there was a typo (name instead of
   nsec3_name, and not freeing the nsec3_name resulted in leak).
- Small fixes in debug output.

refs #1056 @5m

refs #1056 @5m

refs #1056 @25m

- Some usages still remain, they would require more systematic
  changes.

refs #1056 @2h

closes #1059 @10m

refs #1058 @15m

- Modified dname-table API a bit.
- Just switching old node pointer to new node pointer.
- Should not generate any problems.

closes #1058 @30m