Improved sandbox script to delete appropriately

This change collects a list of what files have been deleted in the
repository and removes them from the sandbox via rm.

If those files have since returned (deleted but returned) they will
still be deleted but, since those files will be in your local copy will
be synced to the sandbox.

sandbox.sh

@@ -125,6 +125,13 @@ How do you wish to proceed? [1]"
 
   fi
 
+  # Determine which files have been removed from the repository (as of this head, within the past month) according to git
+  files_to_delete=$(git log --format=format:"" --name-only --since="last month" --diff-filter=D HEAD)
+
+  # Remove all of those files from the destination.  (Note, if a file has since been re-added to the repo it will be uploaded in the next step)
+  rmcmd="ssh $SANDBOX_USER@$SANDBOX_LOCATION 'cd $SANDBOX_PUBLIC_THEMES_FOLDER && rm -f $files_to_delete'"
+  eval $rmcmd;
+
   cmd="rsync -av --no-p --no-times --exclude-from='.sandbox-ignore' --exclude=$ignore_string ./ $SANDBOX_USER@$SANDBOX_LOCATION:$SANDBOX_PUBLIC_THEMES_FOLDER/"
   eval $cmd