[CMake] Add minimal cmake file

Only supports "add_subdirectory" workflow and doesn't
run unit-tests. It generates a INTERFACE cmake target
that other libraries can use to express their dependency
on Boost.ContainerHash and get usage requiremments,
such as the include directory.

CMakeLists.txt

@@ -0,0 +1,23 @@
+# Copyright 2018 Mike Dev
+# Distributed under 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
+
+cmake_minimum_required(VERSION 3.5)
+project(BoostContainerHash LANGUAGES CXX)
+
+add_library(boost_container_hash INTERFACE)
+add_library(Boost::container_hash ALIAS boost_container_hash)
+
+target_include_directories(boost_container_hash INTERFACE include)
+
+target_link_libraries(boost_container_hash
+    INTERFACE
+        Boost::assert
+        Boost::config
+        Boost::core
+        Boost::detail
+        Boost::integer
+        Boost::static_assert
+        Boost::type_traits
+)
+