CMake - introduce directory for external libraries

Author: SiskaPavel

CMakeLists.txt

@@ -9,7 +9,6 @@ project(ipfixprobe VERSION ${VERSION} LANGUAGES CXX C)
 
 include(cmake/build_type.cmake)
 include(cmake/installation.cmake)
-include(cmake/dependencies.cmake)
 
 set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake/modules)
 
@@ -32,4 +31,7 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wpedantic -Wall -Wextra -Wunused -Wconv
 set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -O3 -Werror")
 set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -g -ggdb3")
 
+include(cmake/dependencies.cmake)
+
+add_subdirectory(external)
 add_subdirectory(src)

external/CMakeLists.txt

@@ -0,0 +1,4 @@
+include(FetchContent)
+include(ExternalProject)
+
+set(FETCHCONTENT_QUIET OFF)