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* New Features
* Add image extraction plug-in (843, 1150)
* Add configuration validation feature (973, 1144)
* Improvements
* clustering: change APIs to accept ID-based datum (1155)
* Update Dockerfile to use Ubuntu 14.04 (1146)
* Improve ``--daemon`` option of server and proxy to detach from console (1072, 1148)
* classifier: models are now compatible in standalone and distributed mode (469, 1153)
* Change the default log level to INFO instead of DEBUG (1152)
* Update example configurations (1165)
* Update manpages (1167)
* Update packaging tools (1157)
* Bug fixes
* graph: fix IDs being reused when loading model file to other server instance in standalone mode (1149, 1156)