Add JDK6 compatibility section in EAP docs

Include the content from the attached document in the EAP guides, installation guide would be a better fit.
This contains the setup steps as well as known issues for running EAP with JDK 6.
This is a standalone document for customers.
Please modify title, introduction accordingly to suit the EAP docs.

At his moment only the content for EAP 4.3 is ready. Will provide EAP 4.2 soon.
Note: Some of the known issues in the document might be fixed in the coming weeks. We need not include the fixed ones.