def subtree_init?(path = Dir.pwd)
      res = true
      FalkorLib.config.git[:subtrees].keys.each do |dir|
        res &&= File.directory?(File.join(path, dir))
      end
      res
    end
def subtree_init?(path = Dir.pwd)
      res = true
      FalkorLib.config.git[:subtrees].keys.each do |dir|
        res &&= File.directory?(File.join(path, dir))
      end
      res
    end
Check if the subtrees have been initialized.
 Actually based on a naive check of sub-directory existence