Thread: pgsql: Add SPI_getnspname(), including documentation.

Log Message:
-----------
Add SPI_getnspname(), including documentation.

Modified Files:
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    pgsql/doc/src/sgml:
        spi.sgml (r1.39 -> r1.40)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/spi.sgml.diff?r1=1.39&r2=1.40)
    pgsql/src/backend/executor:
        spi.c (r1.136 -> r1.137)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/spi.c.diff?r1=1.136&r2=1.137)
    pgsql/src/include/executor:
        spi.h (r1.50 -> r1.51)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/executor/spi.h.diff?r1=1.50&r2=1.51)