Define the wire format for the new virDomainCreateWithFlags
API, and implement client and server side of marshaling code.

* daemon/remote.c (remoteDispatchDomainCreateWithFlags): Add
server side dispatch for virDomainCreateWithFlags.
* src/remote/remote_driver.c (remoteDomainCreateWithFlags)
(remote_driver): Client side serialization.
* src/remote/remote_protocol.x
(remote_domain_create_with_flags_args)
(remote_domain_create_with_flags_ret)
(REMOTE_PROC_DOMAIN_CREATE_WITH_FLAGS): Define wire format.
* daemon/remote_dispatch_args.h: Regenerate.
* daemon/remote_dispatch_prototypes.h: Likewise.
* daemon/remote_dispatch_table.h: Likewise.
* src/remote/remote_protocol.c: Likewise.
* src/remote/remote_protocol.h: Likewise.
* src/remote_protocol-structs: Likewise.