Implementation of /because REST endpoint based on recent changes for /recommend
Merge pull request #40 from smarthi/suneel

Implementation of /because REST endpoint
Implementation of /similarityToItem REST endpoint
Merge pull request #42 from smarthi/suneel

Implementation of /similarityToItem REST endpoint
Implementation of /mostSurprising REST endpoint
Merge pull request #43 from smarthi/suneel

Implementation of /mostSurprising REST endpoint
Refactor some common code current endpoints and tests. Update some endpoint javadoc. A few small optimizations