dev-cpp/fkYAML: new package, add 0.4.2

Signed-off-by: Pavel Sobolev <contact@paveloom.dev>

dev-cpp/fkYAML/files/fkYAML-0.4.2-Use-system-Catch2.patch

@@ -0,0 +1,38 @@
+From: Pavel Sobolev <contact@paveloom.dev>
+Subject: [PATCH] Use system `Catch2`.
+
+Signed-off-by: Pavel Sobolev <contact@paveloom.dev>
+
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -32,21 +32,7 @@ if(FK_YAML_CODE_COVERAGE OR FK_YAML_RUN_VALGRIND OR FK_YAML_RUN_CLANG_SANITIZERS
+ endif()
+ 
+ if(FK_YAML_BUILD_TEST OR FK_YAML_BUILD_ALL_TEST)
+-  set(CATCH2_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/thirdparty/catch2")
+-
+-  if(NOT EXISTS ${CATCH2_ROOT_DIR}/CMakeLists.txt)
+-    find_package(Git REQUIRED)
+-    message(STATUS "Fetching git submodule: Catch2")
+-    execute_process(
+-      COMMAND ${GIT_EXECUTABLE} submodule update --init --recursive -- ${CATCH2_ROOT_DIR}
+-      WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+-      RESULT_VARIABLE GIT_SUBMOD_RET)
+-    if(NOT GIT_SUBMOD_RET EQUAL "0")
+-      message(FATAL_ERROR "Failed to fetch Catch2 as a git submodule.")
+-    endif()
+-  endif()
+-
+-  list(APPEND CMAKE_MODULE_PATH "${CATCH2_ROOT_DIR}/contrib")
++  find_package(Catch2 REQUIRED)
+ endif()
+ 
+ ###########################################
+@@ -140,7 +126,6 @@ endif()
+ ###########################
+ 
+ if(FK_YAML_BUILD_TEST OR FK_YAML_BUILD_ALL_TEST)
+-  add_subdirectory(${CATCH2_ROOT_DIR})
+   include(CTest)
+   enable_testing()
+   add_subdirectory(tests)