Cleanup CMake horrors

.gitmodules

@@ -0,0 +1,4 @@
+[submodule "external/google-benchmark"]
+	path = external/google-benchmark
+	url = https://github.com/google/benchmark.git
+

.travis.yml

@@ -66,7 +66,7 @@ before_script:
   - mkdir -p build
   - cd build
   - if [ -n "$GCC_VERSION" -a "$ASAN" == "On" ]; then CXX_FLAGS="${CXX_FLAGS}"; fi
-  - cmake .. -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DCMAKE_CXX_FLAGS="${CXX_FLAGS}"
+  - cmake .. -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DCMAKE_CXX_FLAGS="${CXX_FLAGS}" -DSTL2_BUILD_BENCHMARKS=ON -DBENCHMARK_ENABLE_GTEST_TESTS=OFF
   - make VERBOSE=1 -j${JOBS}
 
 script:

CMakeLists.txt

@@ -32,6 +32,11 @@ install(
     FILES ${PROJECT_BINARY_DIR}/cmcstl2-config.cmake
     DESTINATION lib/cmake/cmcstl2)
 
+if (STL2_BUILD_BENCHMARKS)
+add_subdirectory(external/google-benchmark)
+add_subdirectory(benchmark)
+endif()
+
 add_subdirectory(examples)
 
 enable_testing()

benchmark/CMakeLists.txt

@@ -0,0 +1,14 @@
+# cmcstl2 - A concept-enabled C++ standard library
+#
+#  Copyright Eric Niebler 2018
+#
+#  Use, modification and distribution is subject to the
+#  Boost Software License, Version 1.0. (See accompanying
+#  file LICENSE_1_0.txt or copy at
+#  http://www.boost.org/LICENSE_1_0.txt)
+#
+# Project home: https://github.com/caseycarter/cmcstl2
+#
+
+add_executable(itinerary itinerary.cpp)
+target_link_libraries(itinerary stl2 benchmark)