introduce the vatsim oauth logic

config/config.yaml

@@ -1,4 +1,10 @@
 database:
   host: 'localhost'
   port: 27017
-  name: 'aman'
+  name: 'aman'
+vatsim-auth:
+  base-url: 'https://auth-dev.vatsim.net'
+  token-endpoint: 'oauth/token'
+  user-endpoint: 'api/user'
+  client-id: '461'
+  client-secret: 'kMAuQeIa4TvfZOIZw0t5AA5G5PA0UKTehtSASYdI'