Do not set empty Tags in Medidata XML

[zdavatz]

1. Create a new patient.
2. Do not fill in the following fields:
3. Phone number
4. Email
5. If Phone Number and Email are not there in the patient address, then do not create those XML Tags in the Medidata file.
6. Missing XML Tags will make the XML validate better.
7. Empty, existing XML Tags will make the XML not validate.