[tests] check python and ccm presence when running tests
Merge pull request #22 from datastax/python-ccm-check

[tests] check python and ccm presence when running tests
[RUBY-34] return nil if a value is empty
[ci skip] update CHANGELOG
Merge pull request #23 from datastax/fix-timestamp-decoding

[RUBY-34] return nil if a value is empty
add a regression test for decoding empty buffer
[RUBY-36] default to token-aware dc-aware round robin
Merge pull request #24 from datastax/RUBY-36

Ruby 36