Refactor load test into separate runner

git-svn-id: http://myrrix-recommender.googlecode.com/svn/trunk@513 0d189622-dca1-7e23-9e30-e8815eb7bd2f
Optimization to avoid an array copy and loop for Wu / YTCupu

git-svn-id: http://myrrix-recommender.googlecode.com/svn/trunk@514 0d189622-dca1-7e23-9e30-e8815eb7bd2f
Access matrix in Commons Math directly for a nontrivial speedup

git-svn-id: http://myrrix-recommender.googlecode.com/svn/trunk@515 0d189622-dca1-7e23-9e30-e8815eb7bd2f