Previously, spring-boot required org.json:json to be on the compile
classpath, but it was only there by virtue of it being a transitive
dependency of another of spring-boot’s dependency. This commit makes
it clear that spring-boot has an (optional) dependency on org.json:json
by having an explicit dependency declaration for it. Additionally, the
name of the version property and the alphabetical ordering in
spring-boot-dependencies have been corrected.

Closes gh-3290