The format for /liquibase and /flyway has changed with Spring Boot 1.5.0
to support multiple Flyway/Liquibase beans. With this change we adpot
the new format, but also support the old one.

closes #371

Using an absolut url in $http.get doesn't work when the server.context-path has
been changed for the admin server. Like in all other places a relative url has
to be used.

fixes #256

Adds an application view that displays a list of
Liquibase migrations as retrieved from the /liquibase Actuator
endpoint. The module is conditional on this endpoint being
available.