Merge branch 'nameserver' into development

samples/example.com.zone

src/other/debug.h

src/other/dynamic-array.c

src/other/dynamic-array.h

src/other/skip-list.c

src/other/skip-list.h

src/server/name-server.c

src/server/name-server.h

src/zone/zone-data-structure.c

src/zone/zone-data-structure.h

src/zone/zone-database.c

src/zone/zone-database.h

src/zone/zone-node.c

src/zone/zone-node.h