Reverse order of active profiles before processing

This change harmonizes the profile ordering between spring.profiles.active
(where last one already wins) and SpringApplication.setAdditionalProfiles()
(where the first one has been winning in 1.0.x). Last one wins is the
correct strategy since it mimics a map merge, and also matches the behaviour
of file ordering already defined in spring.config.location and
spring.config.name.

Fixes gh-645