libpqtypes - libpqtypes: update libpqtypes.h so PQgeterror returns a

Log Message:
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update libpqtypes.h so PQgeterror returns a non-const string

Modified Files:
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libpqtypes/src:
libpqtypes.h (r1.15 -> r1.16)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/libpqtypes/libpqtypes/src/libpqtypes.h.diff?r1=1.15&r2=1.16)