When the code_server is about to purge a module it will now issue
asynchronous check_process_code requests to all processes at once
instead of one at a time. These check_process_code operation can
execute in parallel.

* ks/hipe_unified_loader-cleanup/OTP-11301:
  Updated primary bootstrap
  Cleanup of the file

* raimo/linux-network-namespace-sockopt/OTP-11157:
  Document socket option 'netns'
  Rudimentary test
  Make netns option value a string
  Implement netns for SCTP + bugfixes
  Implement netns option for TCP and UDP
  Implement emulator netns support for TCP and UDP

Consisting of three items:
 - Eliminate uses of is_subtype/2 in specs
 - Change module-local void functions to return 'ok' instead of []
 - Make sure there are no dialyzer warnings with --Wunmatched_returns

* fh/start-all/OTP-11250:
  kernel: fix documentation regarding ensure_all_started endtag
  Updated primary bootstrap
  Add application:ensure_all_started/1-2

* fredrik/inet/clarify_doc_address/OTP-10676:
  kernel: fixed specs to inet:ntoa/1
  kernel: changed tests where inet_parse:ntoa/1 was used to inet:parse/1
  kernel: added ntoa documentation and exported it in inet.erl
  kernel: clarified inet:parse_address/1 referrering to old code