Log Message:
Update to 2.8.1

Changelog:
Knot DNS 2.8.1 (2019-04-09)
===========================

Improvements:
-------------
 - Possible zone transaction is aborted by zone events to avoid inconsistency
 - Added log message if no persistent config DB is available during 'conf-begin'
 - New environment setting 'KNOT_VERSION_FORMAT=release' for extended version \ 
suppression
 - Various improvements in the documentation

Bugfixes:
---------
 - Broken NSEC3-wildcard-nonexistence proof after NSEC3 re-salt
 - Glue records under delegation are sometimes signed
 - RRL doesn't work correctly on big-endian architectures
 - NSEC3 not re-salted during AXFR refresh
 - Failed to sign new zone contents if added dynamically #641
 - NSEC3 opt-out signing doesn't work in some cases
 - Broken NSEC3 chain after adding new sub-delegations
 - Redundant SOA RRSIG on slave if RRSIG TTL changed on master
 - Sometimes confusing log error message for NOTIFY event
 - Improper include for LMDB #638

Knot DNS 2.8.0 (2019-03-05)
===========================

Features:
---------
 - New offline-KSK mode of operation
 - Configurable multithreaded DNSSEC signing for large zones
 - Extended ACL configuration for dynamic updates
 - New knotc trigger 'zone-key-rollover' for immediate DNSKEY rollover
 - Added support for OPENPGPKEY, CSYNC, SMIMEA, and ZONEMD RR types
 - New 'double-ds' option for CDS/CDNSKEY publication

Improvements:
-------------
 - Significant speed-up of zone updates
 - Knotc supports force option in the interactive mode
 - Copy-on-write support for QP-trie (Thanks to Tony Finch)
 - Unified and more efficient LMDB layer for journal, timer, and KASP databases
 - DS check event is re-planned according to KASP even when purged timers
 - Module DNS Cookies supports explicit Server Secret configuration
 - Zone mtime is verified against full-precision timestamp (Thanks to Daniel \ 
Kahn Gillmor)
 - Extended logging (loaded SOA serials, refresh duration, tiny cleanup)
 - Relaxed fixed-length condition for DNSSEC key ID
 - Extended semantic checks for DNAME and NS RR types
 - Added support for FreeBSD's SO_REUSEPORT_LB
 - Improved performance of geoip module
 - Various improvements in the documentation

Compatibility:
--------------
 - Changed configuration default for 'cds-cdnskey-publish' to 'rollover'
 - Journal DB format changes are not downgrade-compatible
 - Keymgr no longer prints DS for algorithm SHA-1