Expose helper methods for XML processing
Expose helper methods for XML processing

The `getSchema()` and `validate()` method have both been deprecated, they were never used and remained in a very strange, partly unfinished state. There are no plans to actively use these methods in the core anyway.

See #2646

SoftCreatR/WCF,SoftCreatR/WCF,Cyperghost/WCF,Cyperghost/WCF,MenesesEvandro/WCF,WoltLab/WCF,WoltLab/WCF,WoltLab/WCF,SoftCreatR/WCF,SoftCreatR/WCF,Cyperghost/WCF,Cyperghost/WCF,WoltLab/WCF,MenesesEvandro/WCF,Cyperghost/WCF