Major Description
This constructor is useful when Gremlin Server is being used in an embedded
style and there is a need to share thread pools with the hosting application.
A constructor that can do this has been removed since: https://github.com/apache/tinkerpop/commit/67cd592742cc84cefdb1368a374119e7d4290e1e#diff-38a2e38559996e996423c0ca2ff597fbL128, which results in incompatible with the existing code.
