Port over Linpack and memory bandwidth reporting tools, and put them into the Cloud status (via Heartbeat).

FIXME: LinuxProcFileReader.java should check the actual CPU affinity mask, requires additional import.
PUBDEV-9: Bring back auto-tuning of train_samples_per_iteration based on Linpack and NetworkTest.
PUBDEV-9: Bring back JUnit test for auto-tuning.
Merge branch 'master' of https://github.com/0xdata/h2o-dev