Adtk

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- Formalized the management of releases and pre-releases, including rules of branches and versioning
- Added more rules for developers to the documentation

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- Added many new unit tests, and modified some old unit test
- Removed seaborn from dependencies (use matplotlib built-in style now)
- Fixed a bug in the metric module of dict objects as input
- Fixed a bug in the detector OutlierDetector that output series has dtype object if NaN is present
- Fixed a bug in transformer pipeline that detect and transform methods are confused
- Fixed a bug in pipenet that an aggregator node may crash if its input is from a node where subset contains a single item
- Fixed a bug in pipenet summary that subset column are always "all" even if not
- Some minor optimization of code

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- Changed the parameter `steps` of pipenet from list to dict
- Added method `summary` to pipenet
- Corrected some major algorithmic issues on seasonal decomposition

- Removed STL decomposition transformer, and hence the corresponding option in SeasonalAD detector
- Recreated classic seasonal decomposition transformer

- Updated the demo notebook in the documentation
- Added an option to hide legend in the plotting function
- Added some package setup options for developers
- Fixed an issue of tracking Travis and Coveralls status
- Some minor internal optimization in the code
- Fixed some format issues and typos in the documentation

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- Fixed an issue of tox environments
- Minor spelling/grammar fix in documentation

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- Added support to Python 3.5
- Better unit tests on dependencies
- Minor typo fix in documentation
- Minor code optimization
- Added download statistics to README
- Added coverage test

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- Initial release