IVGCVSW-5365 'Create the TfLite Delegate subdirectory in ArmNN'

* Created delegate sub-directory under armnn
* Created Delegate, ArmnnSubgraph and DelegateOptions classes
* Created cmake files.
* Integrated doctest (under MIT license) as testing framework

Signed-off-by: Sadik Armagan <sadik.armagan@arm.com>
Change-Id: If725ebd62c40a97c783cdad22bca48709d44338c
diff --git a/delegate/cmake/Modules/FindFlatbuffers.cmake b/delegate/cmake/Modules/FindFlatbuffers.cmake
new file mode 100644
index 0000000..13d6f91
--- /dev/null
+++ b/delegate/cmake/Modules/FindFlatbuffers.cmake
@@ -0,0 +1,32 @@
+#
+# Copyright © 2020 Arm Ltd and Contributors. All rights reserved.
+# SPDX-License-Identifier: MIT
+#
+
+include(FindPackageHandleStandardArgs)
+unset(FLATBUFFERS_FOUND)
+
+find_path(Flatbuffers_INCLUDE_DIR
+        flatbuffers/flatbuffers.h
+        HINTS
+            ${FLATBUFFERS_ROOT}/include
+            /usr/local/include
+            /usr/include)
+
+find_library(Flatbuffers_LIB
+        NAMES
+            libflatbuffers.a
+            flatbuffers
+        HINTS
+            ${FLATBUFFERS_ROOT}/lib
+            /usr/local/lib
+            /usr/lib)
+
+## Set FLATBUFFERS_FOUND
+find_package_handle_standard_args(Flatbuffers DEFAULT_MSG Flatbuffers_INCLUDE_DIR Flatbuffers_LIB)
+
+## Set external variables for usage in CMakeLists.txt
+if(FLATBUFFERS_FOUND)
+    set(Flatbuffers_LIB ${Flatbuffers_LIB})
+    set(Flatbuffers_INCLUDE_DIR ${Flatbuffers_INCLUDE_DIR})
+endif()
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