minor change
Merge remote-tracking branch 'origin/handi'
modified performance class
add http connect timeout
Trying to improve the recall of doc
Merged with new http client
add document recall
v0.5
merge from zhuang
Added comments
add doc and concept MAP
Merge remote-tracking branch 'upstream/master' into dev
print out exact answer
Added abstract to document retrieve
Merge remote-tracking branch 'origin/master'
merge
merge
Removed duplicated answer
add answer evaluation
merge from zhuang