Added support for a couple of corner cases in LASSO regression.
A better (corrext?) fix?
Merging changes from madrury.
Fixing a typo
Merge pull request #1 from AlexeyG/master

Bug fixes:
   1. Lambda max would be determined as a Nan because some variables have zero variance (commit 4407e8a)
2. The predict method would crash when all variables were eliminated due to high lambda (commit 794a337)