Add a lambda-friendly version of the filter method since lambdas can only replace interfaces. To make it JDK 8 friendly, it's probably going to be necessary to figure out how to provide alternatives to methods that take a Predicate and overload it with a version that takes a Function<T,Boolean> (which very easily translates to a Predicate instance).
Update the gradle build to use the propdeps plugin to provide "provided" and "optional" dependency scopes. Also restructured the build to more closely conform to the latest spring-framework build.gradle file.