merge with hw3
merge with huan
merger with huan's first part
hw3 4.1 query rep
term frequency per document support
Merge branch 'huiyang' of https://github.com/owwlo/web_search_engine_course
hw3 4.2 query sim
remove common-io library
add documentTermFrequencyMap() method for Indexer
docid->map<term,occ>
add log file
load