moving to using the package object for minimization rather than OptParams
toMultiMap for collections. I need this all the time
Merge remote-tracking branch 'scalanlp/master'
CanZipMapKeyValues. ping @dbtsai
The L1regParam can be configured through anonymous function, and each component can be penalized differently.

This weighted regularization for L1 will be very useful to exclude the intercept from regularization.