Support Column.index
Merge pull request #140 from yongjhih/index

Support Column.index
Throw a runtime exception instead of silently failing when the
framework encounters a model with no default constructor.
Merge pull request #138 from JDeuce/feature-add-exception-on-no-default-constructor

Throw a runtime exception instead of silently failing when the
Merge pull request #1 from pardom/master

updated