Update to Grafana Dashboard for NSB PROX NFVI

Update to Grafana Dashboard for NSB PROX NFVI

JIRA: YARDSTICK-1252

CPU grouping in grafana for better representation
Throughput table is difficult to read as the tests
  run longer the values can overlap
Default time in dashboard should be always last 1hour in
  dashboard (auto refresh can be also checked)
Add one column in table with Gbps throughput (Rx
  Throughput) plus code change in yardstick
Boxes are not aligned and big and small, need to be fixed
  boxes are now aligned,
Added Seperate graphe for LINE Rate

Change-Id: Ief31777c2e7a18aab4bf21fb6ccc0e93a3bb9178
Signed-off-by: Daniel Martin Buckley <daniel.m.buckley@intel.com>