WIP Add panel to hass.io (#46)

* Add poliymare

* Add commit

* add static route

* fix name

* add panel

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "home-assistant-polymer"]
+	path = home-assistant-polymer
+	url = https://github.com/home-assistant/home-assistant-polymer

hassio/api/__init__.py

@@ -1,5 +1,6 @@
 """Init file for HassIO rest api."""
 import logging
+from pathlib import Path
 
 from aiohttp import web
 
@@ -96,6 +97,13 @@ class RestAPI(object):
         self.webapp.router.add_post('/security/totp', api_security.totp)
         self.webapp.router.add_post('/security/session', api_security.session)
 
+    def register_panel(self):
+        """Register panel for homeassistant."""
+        panel_dir = Path(__file__).parents[1].joinpath('panel')
+
+        self.webapp.router.register_resource(
+            web.StaticResource('/panel', str(panel_dir)))
+
     async def start(self):
         """Run rest api webserver."""
         self._handler = self.webapp.make_handler(loop=self.loop)