Added option to add submodules as needed

CMakeLists.txt

@@ -304,6 +304,21 @@ if(QUARTER_BUILD_AWESOME_DOCUMENTATION)
     set(DOXYGEN_TAGFILES_AWESOME "${Coin_DOC_DIR}/html/Coin.tag=../../${_coin_versioned_dir}/html_awesome")
   endif()
 
+  find_package(Git QUIET)
+  if(GIT_FOUND AND EXISTS "${PROJECT_SOURCE_DIR}/.git")
+  # Update submodules as needed
+      option(GIT_SUBMODULE "Check submodules during build" ON)
+      if(GIT_SUBMODULE)
+          message(STATUS "Submodule update")
+          execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init --recursive
+                          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                          RESULT_VARIABLE GIT_SUBMOD_RESULT)
+          if(NOT GIT_SUBMOD_RESULT EQUAL "0")
+              message(FATAL_ERROR "git submodule update --init --recursive failed with ${GIT_SUBMOD_RESULT}, please checkout submodules")
+          endif()
+      endif()
+  endif()
+
 # ############################################################################
 # Setup documentation options
 # ############################################################################