plpsm - plpgpsm: initial get diagnostics statement support

Log Message:
-----------
initial get diagnostics statement support

Modified Files:
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plpgpsm/src:
gram.y (r1.13 -> r1.14)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/gram.y.diff?r1=1.13&r2=1.14)
pl_exec.c (r1.12 -> r1.13)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/pl_exec.c.diff?r1=1.12&r2=1.13)
scan.l (r1.5 -> r1.6)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plpsm/plpgpsm/src/scan.l.diff?r1=1.5&r2=1.6)