WebSocketSecurityConfig now uses .authenticated()

This is a simpler example without being coupled to any specific roles.
Update to Gradle 2.2.1
Update README Dependency Management Section

- Use pom
- Update versions
- Use aggregate pom for release
- Polish repository name
Make JDK 1.5 compatible

Fixes gh-71
Session.getAttribute returns generic type

This prevents the need to cast the attribute values.

Fixes: gh-64
Remove @Override from interface method implementations

Issues: gh-71
EnableWebMvcSecurity->EnableWebSecurity
Add Default Expiration Option to MapSessionRepository

Fixes gh-73
Added Spring Boot Sample

Fixes gh-37
Update Versions
WebSocketRegistryListener handles null Session in SessionDisconnectEvent

Fixes gh-77
Add Spring Security Sample

Fixes gh-68