Add ids to Python FeatureVectorArray

[jparismorgan]

What

Adds an optional ids argument to the Python FeatureVectorArray. Now you can do:

vectors = np.array([[max_val]], dtype=dtype)
ids = np.array([max_val_ids], dtype=dtype_ids)
feature_vector_array = vspy.FeatureVectorArray(vectors, ids)

And also just:

feature_vector_array = vspy.FeatureVectorArray(vectors, ids)

Testing

• Adds a unit test
• In # I am able to update the index using the ids passed in here.