Please make path of HAL explorer adjustable

[ullenboom]

Currently, the HAL explorer is under the root path, but this will collide with web applications. Please make the path adjustable via a configuration property like

spring.data.rest.hal-explorer-base-path=/api

[nuno-aj-aniceto]

this should be property "spring.data.rest.basePath" as it is used for the spring-data-rest paths.

nevertheless, to me, the most relevant point is the servlet context path: server.servlet.context-path

I could tune the application paths with those properties.