Revert "Moved gex.sch into 1.0 directory"

This reverts commit bde83767b9d1c86230edd37b997507b36e53f34e.

Conflicts:
	xsd20130624/ISO19115-3/gex/1.0/gex.sch
	xsd20130624/ISO19115-3/mex/1.0/mex.sch
	xsd20130624/ISO19115-3/mex/1.0/mex.xml