[PATCH] postgresql.conf.sample->postgresql.conf.sample.in

A patch for converting postgresql.conf.sample to 
postgresql.conf.sample.in . This feature allows you to manage the 
contents of postgresql.conf.sample at the configure phase.

Usage example:

     ./configure --enable-foo


configure.in:

     foo_params=$(cat <<-END
       foo_param1 = on
       foo_param2 = 16
     END
     )
     AC_SUBST(foo_params)


postgresql.conf.sample.in:

     @foo_params@


postgresql.conf.sample:

     foo_param1 = on
     foo_param2 = 16

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