refs #1164 @20m

- Converting domain names to lowercase when saving to zone.
  (This will probably remain in the final version too.)
- Temporary converting domain name to lowercase in
  zone_contents_find_dname_hash().

TODO: This should be resolved more systematically. One possible
      solution: save the QNAME converted to lowercase to the packet
      structure and use it for all lookups.

fixes #1164

- Was not saving zone to the ns_xfr_t structure after finished
  transfer.

- This may be related to #1137

Conflicts:
	src/config.h.in

refs #1130 @5m

- Distinguishing when query forwarding is required.
- Creating forward query.

refs #1130 @30m

- The function was moved to nameserver.

refs #1130 @5m

- Random ID not implemented yet (merge required).

refs #1128 @40m

- Implemented xfrin_apply_remove_all_rrsets() and modified
  xfrin_apply_remove() to distinguish the UPDATE cases.
- Added function for removing RRSets from node (wihthout deleting).
- Added function for emptying general tree (without deleting).

refs #1129 @1h15m

refs #1128 @10m

refs #1127 @1h

- RDATA from RRSet are compared in new function.
- Fixed RRSet comparing when WHOLE is requested.

refs #937 @20m

TODO: setting when loading zone from config.

refs #1132 @5m