pgAdmin III commit: Fix config decode of roles and databases in 8.3/8.4

Fix config decode of roles and databases in 8.3/8.4

unnest is available since 9.0, so we need another way to do the same thing.
It's probably not the best way, but it works across releases.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin3.git;a=commitdiff;h=789a6e665be6c7d495d0233c75edeee2a59f9919

Modified Files
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pgadmin/schema/pgDatabase.cpp |   15 +++++++++++----
pgadmin/schema/pgRole.cpp     |   15 +++++++++++----
2 files changed, 22 insertions(+), 8 deletions(-)