cache
add support for numviews and pagerank
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
compress
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
Merge branch 'huiyang' of https://github.com/owwlo/web_search_engine_course
lambda
add columns to show pagerank and numview
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
modi
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
statc
fix bug in PersistentStoreManager
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course

Conflicts:
	src/edu/nyu/cs/cs2580/IndexerInvertedOccurrence.java
bug
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
debug
Merge branch 'huan' of https://github.com/owwlo/web_search_engine_course
bug
single thread