Fixed issue #965

PostgreSQL updates/inserts ignored None/null values.
This is nice for new entries, but not for updates.
Added derive option to allways add these none/null values for Option<>
variables.

This solves issue #965

src/db/models/device.rs

@@ -5,6 +5,7 @@ use crate::CONFIG;
 
 #[derive(Debug, Identifiable, Queryable, Insertable, Associations, AsChangeset)]
 #[table_name = "devices"]
+#[changeset_options(treat_none_as_null="true")]
 #[belongs_to(User, foreign_key = "user_uuid")]
 #[primary_key(uuid)]
 pub struct Device {