Pyspark Params.hasParam should not throw an error

Pyspark Params class has a method hasParam(paramName) which returns True if the class has a parameter by that name, but throws an AttributeError otherwise. There is not currently a way of getting a Boolean to indicate if a class has a parameter. With Spark 2.0 we could modify the existing behavior of hasParam or add an additional method with this functionality.

In Python:

from pyspark.ml.classification import NaiveBayes
nb = NaiveBayes(smoothing=0.5)
print nb.hasParam("smoothing")
print nb.hasParam("notAParam")

produces:
> True
> AttributeError: 'NaiveBayes' object has no attribute 'notAParam'

However, in Scala:

import org.apache.spark.ml.classification.NaiveBayes
val nb  = new NaiveBayes()
nb.hasParam("smoothing")
nb.hasParam("notAParam")

produces:
> true
> false