Fix testdrive samples
FLEX-233 : ClassNotFoundException when Hibernate 4 is on the classpath

A ClassNotFoundException was thrown when Hibernate 4 is on the classpath
but not Spring Flex Hibernate 4 support (same issue for Hibernate 3).

This commit add an additional check against Spring Flex Hibernate 3 and 4 in order
to avoid this error.
Specify spring-expression version
Upgrade to Spring Framework 4.1.0
FLEX-235: Create spring-flex-1.6.xsd