[ADD] create dav_calendar_sync addon

creates new addon dav_calendar_sync to synchronize caldav events on Odoo calendar

dav_calendar_sync/models/dav_server.py

@@ -0,0 +1,19 @@
+import caldav
+from odoo import _, api, fields, models
+
+
+class DavServer(models.Model):
+    _inherit = "dav.server"
+
+    dav_calendar_ids = fields.One2many('dav.calendar', 'dav_server_id', string='Dav Calendars')
+     
+    def compute_dav_calendar_ids(self):
+        calendars = self.get_principal().calendars()
+        for calendar in calendars:
+            values = {
+                "name": calendar.name,
+                "url": calendar.url,
+                "dav_server_id": self.id,
+            }
+            self.env["dav.calendar"].create(values)
+