plproxy - plproxy: Remote 'statement_timeout' config parameter.

Log Message:
-----------
Remote 'statement_timeout' config parameter.

It did not work in 2.0.2 and although it works now,
it could not work in live env as the SET cannot be combined
with main request, thus likely it will be executed on different
backend.

Modified Files:
--------------
    plproxy/doc:
        config.txt (r1.1.1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/doc/config.txt.diff?r1=1.1.1.1&r2=1.2)
    plproxy/expected:
        plproxy_test.out (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/expected/plproxy_test.out.diff?r1=1.3&r2=1.4)
    plproxy/sql:
        plproxy_test.sql (r1.3 -> r1.4)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/sql/plproxy_test.sql.diff?r1=1.3&r2=1.4)
    plproxy/src:
        cluster.c (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/src/cluster.c.diff?r1=1.4&r2=1.5)
        execute.c (r1.7 -> r1.8)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/src/execute.c.diff?r1=1.7&r2=1.8)
        plproxy.h (r1.9 -> r1.10)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/src/plproxy.h.diff?r1=1.9&r2=1.10)