Use stacked area test node graph

Much more interesting information.  The green area should still
make it easy to see if there are immediate available nodes.

Change-Id: I0559bc5cee5f5cfa864d11558818995017169bd0
Add sparklines to pipeline headers

http://en.wikipedia.org/wiki/Sparkline

Change-Id: Ibeef433d57376d256939ecc7a60eff27e03b98b9
Merge "Use stacked area test node graph"
Merge "Add sparklines to pipeline headers"