Took log4j init out of SharkContext.
Merge pull request #167 from rxin/logging

Took log4j init out of SharkContext.
A smarter execution strategy for limit.
Fixed a bug in numPartsToTry calculation.
Overestimate by 50%.
Merge pull request #171 from rxin/limit2

A smarter execution strategy for limit.
Merge branch 'master' of github.com:amplab/shark into ampmaster
Warnings now errors. Disabled cyclomatic complexity