Vectorized cost function evaluator sub-class

[Balaji Pokuri]

Will be needed in situations where execution time is comparable to wait/setup time . In such cases, it will be efficient for the user to run multiple evaluations with a single call of the cost function.

One way to implement is to assign the same PID/JobID for multiple jobs.

For v2.0

[Balaji Pokuri]

Currently it can be dealt with by taking a large allocation of hpc resources and working with LocalAsync Evaluator.

[Balaji Pokuri]

can be taken care of through issue #38