EhCacheFactoryBean does not call set(Sampled)StatisticsEnabled on EhCache 2.7/2.8

Issue: SPR-11265
(cherry picked from commit 73d8f06)
Refined logging to include target class for each transactional method name

Also simplified cache key 'hashCode' implementation, relying on 'equals' to differentiate between same method on different target classes.

Issue: SPR-11267
(cherry picked from commit 82ea9ec)
Polishing

Issue: SPR-11259
(cherry picked from commit f0d2151)