Gets new version

        :param last_version: last version known
        :param last_commit: hash of commit of last version
        :param diff_to_increase_ratio: Ratio to convert number of changes into
        :return: new version

def get_new_version(self, last_version, last_commit,
                        diff_to_increase_ratio):
        """Gets new version

        :param last_version: last version known
        :param last_commit: hash of commit of last version
        :param diff_to_increase_ratio: Ratio to convert number of changes into
        :return: new version
        """

        version = Version(last_version)
        diff = self.get_diff(last_commit, self.get_last_commit_hash())
        total_changed = diff[Diff.ADD] + diff[Diff.DEL]

        version.increase_by_changes(total_changed, diff_to_increase_ratio)
        return version