Merge remote branch 'origin/development' into w40

configure.ac

src/knot/other/error.c

src/knot/other/error.h

src/knot/server/udp-handler.c

src/knot/server/xfr-handler.c

src/knot/server/zones.c

src/knot/zone/zone-dump.c

src/knot/zone/zone-dump.h

src/zcompile/zcompile.c

src/zcompile/zcompile.h

src/zcompile/zparser.y