IVGCVSW-2454 Merge together the pluggable backends work (was in a
separate branch) and master

 * Brings in all the changes done for the pluggable backends
 * Added sub-graph support and tests
 * Added precompiled layer support and tests
 * Moved BackendSettings to a separate file
 * Removed the backend-specific code
 * Ported DebugLayer and associated functionality
 * Included fixes to make those changes work with master

Change-Id: Id7028fa7917527b844628d5aff5732e3d94c0488
diff --git a/tests/ExecuteNetwork/ExecuteNetwork.cpp b/tests/ExecuteNetwork/ExecuteNetwork.cpp
index cfddc38..7d6aafc 100644
--- a/tests/ExecuteNetwork/ExecuteNetwork.cpp
+++ b/tests/ExecuteNetwork/ExecuteNetwork.cpp
@@ -463,9 +463,9 @@
              "as they are expected to be defined in the file for each test in particular.")
             ("concurrent,n", po::bool_switch()->default_value(false),
              "Whether or not the test cases should be executed in parallel")
-            ("model-format,f", po::value(&modelFormat),
+            ("model-format,f", po::value(&modelFormat)->required(),
              "caffe-binary, caffe-text, onnx-binary, onnx-text, tflite-binary, tensorflow-binary or tensorflow-text.")
-            ("model-path,m", po::value(&modelPath), "Path to model file, e.g. .caffemodel, .prototxt,"
+            ("model-path,m", po::value(&modelPath)->required(), "Path to model file, e.g. .caffemodel, .prototxt,"
              " .tflite, .onnx")
             ("compute,c", po::value<std::vector<std::string>>()->multitoken(),
              backendsMessage.c_str())