use LD_LIBRARY_PATH instead of -Djava.library.path
Refactor SparkSubmitDriverBootstrapper.scala
Refactor CommandUtils.scala
review commit
fix comments
Add buildLocalCommand method
topic modeling on Graphx
Refactoring sampling process
Optimizing Performance
Refactoring perplexity method
Add the parameter alphaAS
If we create a lot of big broadcast variables, Spark may hang
review commits
Merge branch 'SPARK-1719' into graphx_bug
Merge branch 'graphx_lda' into graphx_bug