cli: --metadata: add genid= and genid_enable=

The latter is for triggering <genid/> bool XML, which tells libvirt
to auto-allocate a UUID. The cli isn't really XML conformant but
I can't think of anything better that is self advertising

tests/cli-test-xml/compare/virt-install-singleton-config-1.xml

@@ -1,6 +1,7 @@
 <domain type="kvm">
   <name>foobar</name>
   <uuid>00000000-1111-2222-3333-444444444444</uuid>
+  <genid/>
   <description>foobar &amp; baz</description>
   <metadata>
     <libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0">

tests/cli-test-xml/compare/virt-install-singleton-config-2.xml

@@ -1,6 +1,7 @@
 <domain type="kvm">
   <name>foobar</name>
   <uuid>00000000-1111-2222-3333-444444444444</uuid>
+  <genid>e9392370-2917-565e-692b-d057f46512d6</genid>
   <title>my-title</title>
   <description>my-description</description>
   <metadata>
@@ -201,6 +202,7 @@
 <domain type="kvm">
   <name>foobar</name>
   <uuid>00000000-1111-2222-3333-444444444444</uuid>
+  <genid>e9392370-2917-565e-692b-d057f46512d6</genid>
   <title>my-title</title>
   <description>my-description</description>
   <metadata>

tests/clitest.py

@@ -418,6 +418,7 @@ c.add_compare("""
 --clock offset=localtime
 --resource /virtualmachines/production
 --events on_crash=restart
+--metadata genid_enable=yes
 
 --disk none
 --console none
@@ -448,7 +449,7 @@ cell1.distances.sibling0.id=0,cell1.distances.sibling0.value=21,\
 cell1.distances.sibling1.id=1,cell1.distances.sibling1.value=10,\
 cache.mode=emulate,cache.level=3
 --cputune vcpupin0.vcpu=0,vcpupin0.cpuset=0-3
---metadata title=my-title,description=my-description,uuid=00000000-1111-2222-3333-444444444444
+--metadata title=my-title,description=my-description,uuid=00000000-1111-2222-3333-444444444444,genid=e9392370-2917-565e-692b-d057f46512d6
 --boot cdrom,fd,hd,network,menu=off,loader=/foo/bar,emulator=/new/emu,bootloader=/new/bootld,rebootTimeout=3,initargs="foo=bar baz=woo"
 --idmap uid_start=0,uid_target=1000,uid_count=10,gid_start=0,gid_target=1000,gid_count=10
 --security type=static,label='system_u:object_r:svirt_image_t:s0:c100,c200',relabel=yes,baselabel=baselabel

virtinst/cli.py

@@ -1572,6 +1572,8 @@ class ParserMetadata(VirtCLIParser):
         cls.add_arg("name", "name", can_comma=True)
         cls.add_arg("title", "title", can_comma=True)
         cls.add_arg("uuid", "uuid")
+        cls.add_arg("genid", "genid")
+        cls.add_arg("genid_enable", "genid_enable", is_onoff=True)
         cls.add_arg("description", "description", can_comma=True)
         cls.add_arg("os_name", None, lookup_cb=None,
                 cb=cls.set_os_name_cb)

virtinst/guest.py

@@ -144,7 +144,8 @@ class Guest(XMLBuilder):
 
     XML_NAME = "domain"
     _XML_PROP_ORDER = [
-        "type", "name", "uuid", "title", "description", "_metadata",
+        "type", "name", "uuid", "genid", "genid_enable",
+        "title", "description", "_metadata",
         "maxMemory", "maxMemorySlots", "memory", "_currentMemory",
         "blkiotune", "memtune", "memoryBacking",
         "_vcpus", "vcpu_current", "vcpu_placement",
@@ -210,6 +211,8 @@ class Guest(XMLBuilder):
     vcpu_cpuset = XMLProperty("./vcpu/@cpuset")
 
     uuid = XMLProperty("./uuid")
+    genid = XMLProperty("./genid")
+    genid_enable = XMLProperty("./genid", is_bool=True)
     id = XMLProperty("./@id", is_int=True)
     type = XMLProperty("./@type")
     bootloader = XMLProperty("./bootloader")