- Semantic check: missing conversion of next NSEC to lowercase
  when comparing with apex.
- Changed condition when SERVFAIL is returned (no combination
  with any possible Ext RCODE).

Conflicts:
	Knot.files

Only RFC 4034 types are converted to lowercase.
Unified the conversion to one RRSet function used in both zone
parsing and packet parsing.

See merge request !287

 - needed because of master -> slave role switch

Conflicts:
	src/common/namedb/namedb_lmdb.c
	src/common/namedb/namedb_trie.c