AUP3: Removes OD code related to project file handling

This removes all of the OnDemand code embedded throughout
    the main codebase. Individual files related specifically
    to OD have been left in place, but removed from the build.

src/Dependencies.cpp

@@ -610,17 +610,10 @@ bool ShowDependencyDialogIfNeeded(AudacityProject *project,
       if (!isSaving)
       {
          auto msg =
-#ifdef EXPERIMENTAL_OD_DATA
-XO("Your project is currently self-contained; it does not depend on any external audio files. \
-\n\nIf you change the project to a state that has external dependencies on imported \
-files, it will no longer be self-contained. If you then Save without copying those files in, \
-you may lose data.");
-#else
 XO("Your project is self-contained; it does not depend on any external audio files. \
 \n\nSome older Audacity projects may not be self-contained, and care \n\
 is needed to keep their external dependencies in the right place.\n\
 New projects will be self-contained and are less risky.");
-#endif
          AudacityMessageBox(
             msg,
             XO("Dependency Check"),
@@ -632,22 +625,8 @@ New projects will be self-contained and are less risky.");
 
    if (isSaving)
    {
-#ifdef EXPERIMENTAL_OD_DATA
-      wxString action =
-         FileFormatsSaveWithDependenciesSetting.Read();
-      if (action == wxT("copy"))
-      {
-         // User always wants to remove dependencies
-         RemoveDependencies(project, aliasedFiles);
-         return true;
-      }
-      if (action == wxT("never"))
-         // User never wants to remove dependencies
-         return true;
-#else 
       RemoveDependencies(project, aliasedFiles);
       return true;
-#endif
    }
 
    DependencyDialog dlog(pWindow, -1, project, aliasedFiles, isSaving);