- add aarch64 to ONLY_FOR_ARCHS now that it has golang
- drop "MODGO_FLAGS= -tags nosystemd", it was only being passed in for
tests which it didn't change, and didn't do anything else.
- add the default MODGO_FLAGS from go.port.mk to the custom build commands,
to honour MAKE_JOBS/debug settings, and display source files being built
LP64_ARCHS didn't work (GO_ARCHS/LP64_ARCHS aren't available until after
the mk files are pulled in which cause ONLY_FOR_ARCHS to be checked) so
just hardcode amd64 instead.
DNSControl is a system for maintaining DNS zones. It has two parts: a
domain specific language (DSL) for describing DNS zones plus software
that processes the DSL and pushes the resulting zones to DNS providers
such as Route53, CloudFlare, and Gandi. It can talk to Microsoft
ActiveDirectory and it generates the most beautiful BIND zone files
ever.