@Benchmark
    public Edge testAddEdge() {
        return a.addEdge("knows", b);
    }
{@code GraphMutateBenchmark} benchmarks {@link Traversal} and  {@link Graph} mutation methods.

@author Ted Wilmes (http://twilmes.org)
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-tools/gremlin-benchmark/src/main/java/org/apache/tinkerpop/gremlin/process/GraphMutateBenchmark.java