engine: remove SimpleJdbcTemplate

Since spring 3.1, the SimpleJdbcTemplate class does the same as
JdbcTemplate, therefore wrapping JdbcTemplate is not needed anymore and
SimpleJdbcTemplate is deprecated. This patch removes the wrapping
SimpleJdbcTemplates from DAO implementations.

Change-Id: I8782d8790ee682b64d2b14af8840f90b7b7216a9
Signed-off-by: Laszlo Hornyak <lhornyak@redhat.com>