README: Add absent building instructions for specific implementations and the Running section.
README: Add absent building instructions for specific implementations and the Running section.

rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang,rgolubtsov/dnsresolvd-multilang