[xtensor] Add new port (#5196)

ports/xtensor/CONTROL

@@ -0,0 +1,12 @@
+Source: xtensor
+Version: 2019-01-20
+Description: C++ tensors with broadcasting and lazy computing
+Build-Depends: nlohmann-json, xtl
+
+Feature: xsimd
+Description: xtensor with xsimd support
+Build-Depends: xsimd
+
+Feature: tbb
+Description: xtensor with tbb support
+Build-Depends: tbb

ports/xtensor/portfile.cmake

@@ -0,0 +1,51 @@
+# header-only library
+
+include(vcpkg_common_functions)
+
+vcpkg_from_github(
+    OUT_SOURCE_PATH SOURCE_PATH
+    REPO QuantStack/xtensor
+    REF ca0cfdbde852ee61a3ef20076e2733030f3d6479
+    SHA512 d960a3c1c3e6c9250c6bc5ed4e641486980a3ffa4179696eabb92fee50673901324cd2174b76cbd74ab07e6f3c175a26cb564b3087863602c3dce0a83a263da6
+    HEAD_REF master
+)
+
+if("xsimd" IN_LIST FEATURES)
+    set(XTENSOR_USE_XSIMD ON)
+else()
+    set(XTENSOR_USE_XSIMD OFF)
+endif()
+
+if("tbb" IN_LIST FEATURES)
+    set(XTENSOR_USE_TBB ON)
+else()
+    set(XTENSOR_USE_TBB OFF)
+endif()
+
+vcpkg_configure_cmake(
+    SOURCE_PATH ${SOURCE_PATH}
+    PREFER_NINJA
+    OPTIONS
+        -DXTENSOR_USE_XSIMD=${XTENSOR_USE_XSIMD}
+        -DXTENSOR_USE_TBB=${XTENSOR_USE_TBB}
+        -DXTENSOR_ENABLE_ASSERT=OFF
+        -DXTENSOR_CHECK_DIMENSION=OFF
+        -DBUILD_TESTS=OFF
+        -DBUILD_BENCHMARK=OFF
+        -DDOWNLOAD_GTEST=OFF
+        -DDOWNLOAD_GBENCHMARK=OFF
+        -DDEFAULT_COLUMN_MAJOR=OFF
+        -DDISABLE_VS2017=OFF
+)
+
+vcpkg_install_cmake()
+
+vcpkg_fixup_cmake_targets(CONFIG_PATH lib/cmake/${PORT})
+
+file(REMOVE_RECURSE ${CURRENT_PACKAGES_DIR}/debug ${CURRENT_PACKAGES_DIR}/lib)
+
+# Handle copyright
+configure_file(${SOURCE_PATH}/LICENSE ${CURRENT_PACKAGES_DIR}/share/${PORT}/copyright COPYONLY)
+
+# CMake integration test
+vcpkg_test_cmake(PACKAGE_NAME ${PORT})