Merge pull request #6 from fundakol/refactoring

Refactoring #minor

return None instead of raise NoSuchElementException

fix: comprehension list does not work with Container class

DataTable2 (#5)

* Added another version of TableContainer

* added unit tests for TableContainer class

* refactoring DataTable

* updated setup.py and README.md

updated setup.py

refactoring

updated readme, setup.py

updated readme