libvirt follows a convention where structure types used in its API are
named "remote_nonnull_domain", and optional values for those structures
are called "remote_domain". The generator was translating these into go
names like "NonnullDomain" and "Domain". In go this seems unnatural, and
doesn't match the way the pre-generator version of go-libvirt named
things. So this commit changes the names: "remote_nonnull_domain" will
now be "Domain" in go; "remote_domain" will be "OptDomain". This pattern
is applied to all types.
- Bump the minimum libvirt version from 1.2.2 to 1.2.12, because
virDomainDefineXMLFlags wasn't introduced until that version.
- Use the correct format for the generated file notice, so that golint
ignores the generated files.
