Adding LDAP Syncronization (#3219)

config/config.json

@@ -147,6 +147,7 @@
         "UsernameAttribute": "",
         "NicknameAttribute": "",
         "IdAttribute": "",
+        "SyncIntervalMinutes": 60,
         "SkipCertificateVerification": false,
         "QueryTimeout": 60,
         "LoginFieldName": ""