autodoc - autodoc: Add -m <regex> to only output structures or functions

Log Message:
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Add -m <regex> to only output structures or functions matching a specific regex (Simon Michael)

Tidy code along the way.

Modified Files:
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autodoc:
postgresql_autodoc.pl (r1.23 -> r1.24)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/autodoc/autodoc/postgresql_autodoc.pl.diff?r1=1.23&amp;r2=1.24)