[dnssec] KASP dir, write keytag into zone config
[dnssec] keymgr, initialize hardcoded keystore
[dnssec] keymgr, implement "keystore list" command
[dnssec] keymgr, fix missing newlines in error messages
[dnssec] example program, genzonekey

Generates RSA-SHA-256, 512 bit, ZSK key for a zone in KASP.