oledb - oledb: Fix compilation errors when upgrading the Platform SDK

Log Message:
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Fix compilation errors when upgrading the Platform SDK with Visual Studio 6

Modified Files:
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oledb:
INSTALL (r1.6 -> r1.7)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/oledb/oledb/INSTALL.diff?r1=1.6&r2=1.7)
PgCommand.cpp (r1.22 -> r1.23)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/oledb/oledb/PgCommand.cpp.diff?r1=1.22&r2=1.23)
PgDBSchemaRowsetImpl.h (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/oledb/oledb/PgDBSchemaRowsetImpl.h.diff?r1=1.4&r2=1.5)