First cut implementation of Streaming UI.
Added network receiver information to the Streaming UI.
Added basic stats to the StreamingUI and refactored the UI to a Page to make it easier to transition to using SparkUI later.
Added last batch processing time to StreamingUI.
Added Apache licenses.
[SPARK-1398] Removed findbugs jsr305 dependency

Should be a painless upgrade, and does offer some significant advantages should we want to leverage FindBugs more during the 1.0 lifecycle. http://findbugs.sourceforge.net/findbugs2.html

Author: Mark Hamstra <markhamstra@gmail.com>

Closes #307 from markhamstra/findbugs and squashes the following commits:

99f2d09 [Mark Hamstra] Removed unnecessary findbugs jsr305 dependency
Minor style updates.
Merge remote-tracking branch 'apache-github/master' into streaming-web-ui
Merge branch 'streaming-web-ui' of github.com:tdas/spark into ui-refactor
End of file new lines, indentation, and imports (minor)