[SPARK-18929][ML] Add Tweedie distribution in GLM

## What changes were proposed in this pull request?
I propose to add the full Tweedie family into the GeneralizedLinearRegression model. The Tweedie family is characterized by a power variance function. Currently supported distributions such as Gaussian, Poisson and Gamma families are a special case of the Tweedie https://en.wikipedia.org/wiki/Tweedie_distribution.

yanboliang srowen sethah

Author: actuaryzhang <actuaryzhang10@gmail.com>
Author: Wayne Zhang <actuaryzhang10@gmail.com>

Closes #16344 from actuaryzhang/tweedie.

Author: actuaryzhang