make SplFileObject__fgetcsv.csv not be shared by 8 tests

Reviewed By: @JoelMarcey

Differential Revision: D1480793
Enable file XML external entities for frameowrk tests

Summary: refs facebook/hhvm#3375

Doctrine2 uses these for some of its' tests. Still not back at 100% though.

Reviewed By: @JoelMarcey

Differential Revision: D1482233