Set up Gradle build for yogacore

Summary:
I put the CMake file in the root directory to avoid moving the actual `yoga/`
dir around, but created a directory for the Android library manifest nonsense
so it works as its own module you can depend on.

Reviewed By: emilsjolander

Differential Revision: D4913601

fbshipit-source-id: 582064264cf0b6b69c03d0e72ed9dd22d217dd16

CMakeLists.txt

@@ -0,0 +1,17 @@
+#
+# Copyright (c) 2014-present, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+#
+
+cmake_minimum_required(VERSION 3.4.1)
+
+set(CMAKE_VERBOSE_MAKEFILE on)
+
+file(GLOB yogacore_SRC yoga/*.c)
+add_library(yogacore STATIC ${yogacore_SRC})
+
+target_link_libraries(yogacore android log)