replace from_data with from_datum to be consistent with recommender
Merge pull request #148 from jubatus/fix-nn-method-name

Replace *_from_data with *_from_datum (API reference)
migrate logger from google-glog to log4cxx
fix default thread number of proxy
Merge pull request #151 from jubatus/fix-default-threads

Fix default number of threads in proxy
Merge pull request #150 from jubatus/migrate-logger

migrate logger from google-glog to log4cxx
fix for regexp dependency