GitHub #292 Move BackendRegistry.hpp to the public API

 * Moved to BackendRegistry.hpp include/armnn
 * Updated makefiles and sources accordingly

Signed-off-by: Matteo Martincigh <matteo.martincigh@arm.com>
Change-Id: I4d83abb581d523218a880c879fcf30c9611f7fd7
diff --git a/src/armnn/Network.cpp b/src/armnn/Network.cpp
index 1339a6e..a708361 100644
--- a/src/armnn/Network.cpp
+++ b/src/armnn/Network.cpp
@@ -14,13 +14,13 @@
 
 #include <backendsCommon/CpuTensorHandle.hpp>
 #include <backendsCommon/WorkloadFactory.hpp>
-#include <backendsCommon/BackendRegistry.hpp>
 #include <backendsCommon/IBackendInternal.hpp>
 #include <backendsCommon/TensorHandleFactoryRegistry.hpp>
 
 #include <armnn/Exceptions.hpp>
 #include <armnn/Utils.hpp>
 #include <armnn/TypesUtils.hpp>
+#include <armnn/BackendRegistry.hpp>
 
 #include <fcntl.h>
 #include <algorithm>