put the carl-config cmake in the right spot

resources/3rdparty/carl/CMakeLists.txt

@@ -0,0 +1,25 @@
+project(carlext)
+cmake_minimum_required(VERSION 3.3)
+include(ExternalProject)
+
+option(STORM_3RDPARTY_BINARY_DIR "3rd party bin dir")
+
+message(STORM_3RDPARTY_BINARY_DIR: ${STORM_3RDPARTY_BINARY_DIR})
+
+ExternalProject_Add(carl-config
+	GIT_REPOSITORY https://github.com/smtrat/carl
+        GIT_TAG master
+	PREFIX here
+	SOURCE_DIR source_dir
+	BINARY_DIR ${STORM_3RDPARTY_BINARY_DIR}/carl
+	CMAKE_ARGS -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER} -DBOOST_INCLUDEDIR=${Boost_INCLUDE_DIRS} -DBOOST_LIBRARYDIR=${Boost_LIBRARY_DIRS} -DBoost_NO_SYSTEM_PATHS=1 -DEXPORT_TO_CMAKE=0 -DUSE_CLN_NUMBERS=1 -DCMAKE_SKIP_INSTALL_ALL_DEPENDENCY=1 -DCMAKE_INSTALL_PREFIX:PATH=${STORM_3RDPARTY_BINARY_DIR}/carl 
+        BUILD_IN_SOURCE 0
+        LOG_UPDATE OFF
+        LOG_CONFIGURE OFF
+        BUILD_COMMAND "" # Disable build step.
+	INSTALL_COMMAND "" # Disable install step too.
+)
+add_custom_target(build-carl)
+add_dependencies(build-carl carl-config)
+
+message("done")