Merge "Enable heat context to support existing network"

diff --cc yardstick/benchmark/contexts/heat.py
Simple merge

diff --cc yardstick/orchestrator/heat.py
Simple merge

diff --cc yardstick/tests/unit/benchmark/contexts/test_heat.py
Simple merge

diff --cc yardstick/tests/unit/benchmark/contexts/test_model.py
Simple merge

diff --cc yardstick/tests/unit/orchestrator/test_heat.py
Simple merge