Add hostname into version API call (#748)

hassio/api/version.py

@@ -4,7 +4,7 @@ import logging
 from .utils import api_process
 from ..const import (
     ATTR_HOMEASSISTANT, ATTR_SUPERVISOR, ATTR_MACHINE, ATTR_ARCH, ATTR_HASSOS,
-    ATTR_CHANNEL)
+    ATTR_CHANNEL, ATTR_HOSTNAME)
 from ..coresys import CoreSysAttributes
 
 _LOGGER = logging.getLogger(__name__)
@@ -20,6 +20,7 @@ class APIVersion(CoreSysAttributes):
             ATTR_SUPERVISOR: self.sys_supervisor.version,
             ATTR_HOMEASSISTANT: self.sys_homeassistant.version,
             ATTR_HASSOS: self.sys_hassos.version,
+            ATTR_HOSTNAME: self.sys_host.info.hostname,
             ATTR_MACHINE: self.sys_machine,
             ATTR_ARCH: self.sys_arch,
             ATTR_CHANNEL: self.sys_updater.channel,