Revert "Make CInterface exported functions be contained in .h files, instead of .cpp."

This reverts commit 9abdbecd

CMakeLists.txt

@@ -28,7 +28,7 @@ if (NOT WINDOWS)
 endif()
 
 # Grab all cpp and hpp files in our source directories.
-file(GLOB_RECURSE SRC_FILES "src/*.cpp" "src/*.hpp" "CInterface/*.cpp" "CInterface/*.hpp" "CInterface/*.h")
+file(GLOB_RECURSE SRC_FILES "src/*.cpp" "src/*.hpp" "CInterface/*.cpp" "CInterface/*.hpp")
 add_library(Arbutils ${LIBTYPE} ${SRC_FILES})
 target_precompile_headers(Arbutils PUBLIC src/Precompiled.hxx)