some minor change on adarank functions
- add graph laplacian regulizer cost
  -These code pass a small sample sanity check #set beta=0 the output is    same as no graph regulizer.
- revise the sort method to break tie with id
1. Done with graph laplacian with minor performance gain
2. Fixed the comparison function to be keep 9 digits after dot.
add time information regulization
add 13 new features
add options to replace weak ranker from feature to ranking
add new simulation scripts