added new util methods:
  def rmext_inline_or_on_main_q(&block)
  def rmext_block_on_main_q(block, *args)
and some experimental methods:
  def rmext_debounce_on_next_runloop(unique_id, run_immediately, &block)
  def rmext_debounce_selector_on_next_runloop(selector, run_immediately)
  def rmext_debounced(method_name, seconds, *args)
bump