#32 - Made test classes named Abstract… abstract classes.
#33 - Renamed variable for CartItems to item.
#34 - Move to Travis container infrastructure and enable resource caching.
Upgraded to Salespoint 6.1. 

Upgraded to Spring Boot 1.2.0.RELEASE. Removed obsolete plugin declarations and customizations from pom.xml.

Simplified application configuration by using the newly introduced @EnableSalespoint annotation. Switched to UserAccountManager.findByUsername(…). Added Apache license headers where missing.

Switched to logging configuration in application.properties.