- RRSIGs from node are added to rrinfo section.
- When putting RRSIGs for each section, proper RRSIGs for each RRSet are syntesized and later freed.

closes #204

- Added new public alloc helper functions to mempattern.h.
- RRSet owners are not allocated using memctx, because they might be dropped later and because DNAME has no memctx API.
- Only packet had its own memctx at the time of writing. Later, most RRSet operations should use custom allocators, for now, no allocator is used.

Closes #184

value returned by rrset_rdata_pointer() is expected to be nonzero

Previous expectation was that answer names suffix usually matches
QNAME. This doesn't work so well for example for root zone or transfers.
New expectation is that the name suffix is usually similar to previous
name, as they are likely to be grouped together.

Should be obsolete now and should work without them.

refs #168

Not actually used in the code, but was broken.

(Chance to win a beer is included in this commit.)

refs #4

 - DNAMEs in RRSets are now compared using memcmp
 - Modified DNSSEC dump parameters (no wrap ...)
 - Removed double rollback

Refs #4

CID: 1086926

CID: 1086927

Coccinelle patch performing most changes included.

Not optimal, uses existing interface for RRSet merging.

refs #4

Allows to create a new emtpy RRSet given another RRSet as a template.

 - added a debug message to rrset_new()

Refs #4