Added PostgreSQL 9 support.

See 1eccd.
Added pgsql.app.
Added the field vcard.server into pg schema. Fixed string escaping.
username text => username varchar(250). Fixed bytea hex-escaping.
Added pgsql to reltool.config.
Merged with arc-mod-mam-release. Monitor ODBC workers and delete crashed ones from Mnesia.
Merge remote-tracking branch 'upstream/master' into arc-mod-mam-only
Made tls_drv permanent.
Applied small optimizations in SQL escaping.

Moved the body of the functions ejabberd_odbc:escape/1 and ejabberd_odbc:escape_like/1
into odbc_queries.
Use binaries for ODBC queries. Added odbc_queries:update_set_t/3.
Deleted unused mysql:quote/1.
Fixed comments.
Fixed a crash in ejabberd_users:is_stored_user_exists/1 in case, when the anonymous auth is disabled.
Improved mysql driver.

Rewrote asciz/1 using standard library functions.
Send a query as an iolist into a socket.
Replaced strings with binaries. Made bxor_binary/2 shorter.
Use binaries for attributes in ODBC.
Ignore apps/ejabberd/include/XmppAddr.hrl
Made mod_mam_muc:restore_dump_file/1 less strict.
Fixed JID escaping (see querying_for_all_messages_with_jid in CT).
Do not add empty queryid attribute.
Merge branch 'upstream/master' into arc-mod-mam-only