Update logfile ownership before dropping privileges.
knotc respects 'control' section from configuration

Configuration can still be overriden using the command
line parameters.
Fixed debug build.
Implemented 'zonestatus' remote command.

Prints zone status in following format:
<name> | type={master,slave} | serial=N | <state>
Add test for recvmmsg MSG_WAITFORONE

Change-Id: I77615a328dce98e39964c567b55cf7c4dca331e2
Fixed define check for _GNU_SOURCE
Fixed AC_LANG_PROGRAM call missing braces.
Merge branch 'recvmmsg' into release
Remove empty block in --enable-lto, this should fix older autoconf

Change-Id: I414a84fd02871bf78445009a82adfd2e355d67ce
Hopscotch hashing for resolving collisions in RRL.

The idea is to insert colliding items in the H distance of
the original hash value. H must be chosen to accomodate log(N)
items, we use sizeof(unsigned). Unlike in linear probing,
lookup is always in constant time and doesn't require
extra memory and chaining costs as in external chaining.
Extra memory is just sizeof(unsigned) per bucket.
Builtin __builtin_ctz() is used for fast hop lookup.

Herlihy, Maurice and Shavit, Nir and Tzafrir, Moran (2008).
"Hopscotch Hashing". DISC '08: Proceedings of the 22nd
international symposium on Distributed Computing.
Arcachon, France: Springer-Verlag. pp. 350--364.
http://people.csail.mit.edu/shanir/publications/disc2008_submission_98.pdf
Possible leak fix.

- Copied nodes were not freed.
Changed freeing traversal to recursive.

- Postorder was used in master branch.
Switch nodes in DNAMEs also for RRSIGs.
Added missing rrset_deep_free after merge.

- there are more, but not sure if it's needed everywhere.
Small fixes.
Fixed a leak and wrong deletion of added RRSIGs.

- Added free function, that does not free RRSIG.
Small fix.
Small fixes in DDNS.
Copy SOA with DNAMEs too.
Small changes.