Review ox attributes usage, imports and sync scripts

[jgomer2001]

Let's do some maintainance/cleaning of scripts:

• There are several custom scripts that are still using **ox*** attributes (the most notorius example is the otp script that uses oxExternalUid)
• As far as I can see, imports of ServerUtil class are wrong
• There are usage of RestEasy3 classes (see https://github.com/GluuFederation/oxAuth/issues/1597)
• The scripts contents is jans-auth-server integration folder have differences wrt scripts in this repo (for instance, otp again). I vote for removing deprecated scripts and use jans-setup repo to store scripts only.

[jgomer2001]

https://github.com/JanssenProject/jans/issues/777 (I tried to make main scripts conform in this issue)