Update to yaml-cpp 0.6.3

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

CMakeLists.txt

@@ -8,8 +8,6 @@ option(FORCE_BUILD_VENDOR_PKG
 
 find_package(ament_cmake REQUIRED)
 
-set(PACKAGE_VERSION "1.0.0")
-
 macro(build_yaml_cpp)
   set(extra_cmake_args)
   set(YAML_C_FLAGS ${CMAKE_C_FLAGS})
@@ -43,14 +41,9 @@ macro(build_yaml_cpp)
   endif()
 
   include(ExternalProject)
-  # This specific version (past the current latest release of 0.5.3) is required to make
-  # yaml-cpp relocatable, hopefully it is released again soon.
-  # See: https://github.com/jbeder/yaml-cpp/pull/538
-  # Latest release fails to compile on recent visual studio (VS2017 v15.8.1)
-  # See: https://github.com/jbeder/yaml-cpp/pull/597
-  ExternalProject_Add(yaml_cpp-0f9a586
-    URL https://github.com/jbeder/yaml-cpp/archive/0f9a586ca1dc29c2ecb8dd715a315b93e3f40f79.zip
-    URL_MD5 ec76c27ebd07d5178cbe85b773df8e62
+  ExternalProject_Add(yaml_cpp-0.6.3
+    URL https://github.com/jbeder/yaml-cpp/archive/yaml-cpp-0.6.3.tar.gz
+    URL_MD5 b45bf1089a382e81f6b661062c10d0c2
     TIMEOUT 600
     LOG_CONFIGURE ${should_log}
     LOG_BUILD ${should_log}