* richcarl/erts/erl_init-cleanup/OTP-15336:
  sasl: Order systools_make:preloaded modules alphabetically
  Update preloaded modules
  Move calling on_load for preloaded modules to erl_init
  Make erl_init.c pass the boot module to erl_init.beam
  Remove obsolete comment text
  Remove undocumented and unused -# display_items emulator option
  Remove broken and undocumented boot function emulator option
  Replace remaining references to otp_ring0 with erl_init
  Drop otp_ring0, using erl_init instead
  Update preloaded modules
  Add erl_init module

Conflicts:
	erts/emulator/beam/erl_init.c
	erts/preloaded/ebin/erl_prim_loader.beam
	erts/preloaded/ebin/erl_tracer.beam
	erts/preloaded/ebin/erlang.beam
	erts/preloaded/ebin/erts_code_purger.beam
	erts/preloaded/ebin/erts_dirty_process_signal_handler.beam
	erts/preloaded/ebin/erts_internal.beam
	erts/preloaded/ebin/erts_literal_area_collector.beam
	erts/preloaded/ebin/init.beam
	erts/preloaded/ebin/otp_ring0.beam
	erts/preloaded/ebin/prim_buffer.beam
	erts/preloaded/ebin/prim_eval.beam
	erts/preloaded/ebin/prim_file.beam
	erts/preloaded/ebin/prim_inet.beam
	erts/preloaded/ebin/prim_zip.beam
	erts/preloaded/ebin/zlib.beam

I did not find any legitimate use of "can not", however skipped
changing e.g RFCs archived in the source tree.

* bugfixes
* add first test
* remove unused code