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* Sem-Ver: feature Add a new get_severity_description_rating_dict to cvss v2 and v3 calculators and use it in the get_severity_description methods
* Add a test for the severity description ranges of cvss v2
* add travis-ci build status for master to the readme file
* Update the readme file
* Tweak the readme file slightly
* Rename the README file
* Use pbr