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* Updated docs; added test_coverage make commandl updated travis cfg.
* Added new SimpleField validator feature -> it will be replace 'type'
* Added strip_kwargs method for DictEmbeddedDocument. [Maksim
* Models refactoring, improve readability; added .coveragerc. [Maksim
* Rename _type -> type SimpleField attribute. [Maksim Ekimovskii]
* Fix DictEmbeddedDocument type casting; Updated tests; Updated
* Updated validators, integrate it to field setter and document
* Rewritten field storage logic to prevent memory leaks, store all