Update Spring sample application

Prior to this commit, the sample application used for Techempower
benchmarks was using spring-framework 3.2.1, manually managing
Hibernate sessions, and old app configuration.

This commit updates this sample application.
Spring projects were added/updated:
* Spring-Framework 4.0.0.RC1
* Spring Boot
* Spring Data JPA

Application layout was updated as well, using:
* Spring Boot App launcher
* Spring Data repositories
* Full Java Configuration
Simplified boot application
Merge pull request #1 from nebhale/bhale

Ben's changes