OTP-12845

* bruce/change-license:
  fix errors caused by changed line numbers
  Change license text to APLv2

* anders/diameter/18/OTP-12588:
  vsn -> 1.10
  Remove dead upgrade-related code
  Update appup for 18
  Fix release note typo
  Fix comment typo

* anders/diameter/sctp/OTP-12768:
  Fix connection timeouts in test transports
  Fix start order of alternate transports
  Log discarded answers
  Ensure accepting processes are first in, first out
  Remove upgrade-related code
  Be less parallel in traffic suite
  Increase send/receive buffers for testsuite SCTP listeners
  Decrease unnecessarily long testsuite timetraps
  Simplify accepting transport start
  Simplify peeloff signaling
  Simplify socket close at terminate
  Don't monitor listener after peeloff
  Don't receive initial messages out of order
  Remove assumption that SCTP association ids will be unique

* anders/diameter/grouped_errors/OTP-12721:
  Fix decode of Grouped AVPs containing errors
  Simplify logic
  Simplify logic

Without a timeout, TCP/SCTP connect can take some time to fail, which
resulted in failures in the pool suite after the parent commit fixed the
previously faulty sctp-first-then-tcp connect.

A transport configured with diameter:add_transport/2 can be passed
multiple transport_module/transport_config tuples in order to specify
alternate configuration, modules being attempted in order until one
succeeds. This is primarily for the connecting case, to allow a
transport to be configured to first attempt connection over SCTP, and
then TCP in case SCTP fails, with configuration like that documented:

  {transport_module, diameter_sctp},
  {transport_config, [...], 5000},
  {transport_module, diameter_tcp},
  {transport_config, [...]}

If the options are the same in both cases, another possibility would be
configuration like this, which attaches the same transport_config to
both modules:

  {transport_module, diameter_sctp},
  {transport_module, diameter_tcp},
  {transport_config, [...], 5000},

However, in this case the start order was reversed relative to the
documented order: first tcp, then sctp. This commit restores the
intended order.

OTP-12851

Not needed with the parent commit's restart_application.

To diameter_lib:log/4, which was last motivated in commit 39acfdb0.