[urgent][fix] PayPal payemnt fix

* [fix] paypal sandboxing to test dummy payments

* [fix] sandbox testing for razorpay

[path][fix] paypal integration

* [fix] refactor integration services

* [fix] patch fix

* [fix] added redirect url.

* [fix] custom redirect to and reditect message for paypal and service setup information

* [minor][fix] remove ldap dependancy from requirements

* [refactor] scheduler log is now error log

* [minor] new naming series

* [fix] engine

* [fix] saved by tests

[minor][fix] razorpay payment

* [enhancement] integration borker and controller

* [minor][fix] parameter naming changes

* [fix] common scheduler for integration service

* [fix] integrations

* [patch] patch to move payment gateway in Integration Service

* [fix] add payment success, cancel and failuer handling pages

* [enhancment] dropbox integration merged in integration services

* provision to add custom parameters

* [fixes] patch fix to setup dropbox settings

* [fixes] removed dropbox backup, api usage note for paypal and razorpay

* [minor][fix] deprecate service events

* [fix] return type fix for checkout urls

* [fix] add custom settings via patch for dropbox backup frequency

* [fix] remove gride editting

* [enhance] ldap based login

* [enhance] login via ldap credentails

* [commit] remove parameter table, save params as json dict