Shows totals for shuffle data and CPU time in Stage, homepage overviews including active time
Split Shuffle Activity overview column for read/write
Displys shuffle read/write only if exists, wraps if statements, trims old vals, grabs current time once
Made metrics Option instead of Some, fixed NullPointerException
Current time called once with value now
Moved val now to render
Cleaned up code based on pwendell's suggestions
Improve catch scope and logging for client stop()

This does two things:
1. Catches the more general `TimeoutException`, since those can be thrown.
2. Logs at info level when a timeout is detected.
Log executor on finish
Slight wording change
Fixed outdated bugs
Merge pull request #741 from pwendell/usability

Fix two small usability issues
Alphabetized imports
Remove duplicate loss history and clarify why.
Also some minor style fixes.
Merge pull request #735 from karenfeng/ui-807

Totals for shuffle data and CPU time
Moved DeployMessage's into its own DeployMessages object.
Also renamed MasterState to MasterStateResponse and WorkerState to WorkerStateResponse for clarity.
Open up Job UI ports (33000-33010) on EC2 clusters
Removed Cache and SoftReferenceCache since they are no longer used.
Moved block manager messages into BlockManagerMessages object.
Moved all StandaloneClusterMessage's into StandaloneClusterMessages object.