Added support for the JCA 1.7 getActivationName() method

Issue: SPR-11067
Revised @Bean processing rules

@Bean method metadata is always being picked from the most concrete subclass; @Bean method overloads are allowed within the same config class as well; and @Bean overrides and overloads work with 'allowBeanDefinitionOverriding'=false now.

Issue: SPR-10992
Issue: SPR-11025
Polishing (along with SPR-10992)