Restructure "src/" folder

Moving files from the "src/" folder into "src/legacy", "src/macro-core",
and "src/utils" was necessary as it was becoming a bit too cluttered.

cmake/AdvSSHelpers.cmake

@@ -246,8 +246,11 @@ function(setup_advss_plugin target)
   endforeach()
 
   # General includes
-  target_include_directories(${target}
-                             PRIVATE "${ADVSS_SOURCE_DIR}/src/headers")
+  target_include_directories(
+    ${target}
+    PRIVATE "${ADVSS_SOURCE_DIR}/src" "${ADVSS_SOURCE_DIR}/src/legacy"
+            "${ADVSS_SOURCE_DIR}/src/macro-core"
+            "${ADVSS_SOURCE_DIR}/src/utils" "${ADVSS_SOURCE_DIR}/forms")
 endfunction()
 
 function(install_advss_plugin_dependency)

cmake/version.cpp.in

@@ -1,4 +1,4 @@
-#include "headers/version.h"
+#include "version.h"
 #define GIT_SHA1 "@GIT_SHA1@"
 #define GIT_TAG "@GIT_TAG@"
 const char g_GIT_SHA1[] = GIT_SHA1;