escript:foldl/3 was not completely adapted to the changes introduced
in 6af2ac91005276add18b1c9bbf4c8fe4f8c6e040.
A partial fix has already been applied by Hakan Mattson in
4ec4a06edb5baaa0af2840943230c4a0be3a93cf.

Signed-off-by: Tuncer Ayaz <tuncer.ayaz@gmail.com>

* jn/supervisor_child_count_only:
  Add count_children/1 to supervisor.erl to determine the number of

OTP-8436  Added supervisor:count_children/1 to count the number of children
          being managed without the memory impact of which_children/1.
          (Thanks to Jay Nelson.)

* ks/stdlib-cleanups:
  stdlib: clean up as suggested by tidier

OTP-8435: ks/stdlib-cleanups

children being managed without the memory impact of which_children/1

The function which_children/1 returns a list of the child processes
currently being supervised, but it has the penalty of creating a new
list thereby consuming more memory.  In low memory situations it is
often desirable to know which supervisor may have generated many
processes, but the act of discovering the culprit should not cause the
node to crash (or worse a different node if the kernel kills one
randomly).  The new function count_children/1 can give an indication
of which supervisor is taxing resources the most without adding to the
burden.  Rather than creating a new list, it walks the supervisor's
internal children structure using an accumulator function so that any
used memory can be incrementally collected yet the resulting count can
still be obtained.

The return result of count_children/1 is a property list of counts
containing:
  - {specs, Total_Num_Child_Specs}
  - {active, Num_Active_Child_Processes_Of_Supervisor_Or_Worker_Type}
  - {supervisors, Num_Supervisor_Type_Children_Including_Dead_Processes}
  - {workers, Num_Worker_Type_Children_Including_Dead_Processes}

This patch was made in response to mailing list discussions of the
problem diagnosing heavily taxed production systems.  I cannot find
the original request, but http://www.erlang.org/cgi-bin/ezmlm-cgi/4/35060
is my original post of the patch.

          prompt strings (io:get_line/{1,2}). io_lib is also updated to
          format prompts with the 't' modifier (i.e. ~ts instead of ~s).

* ks/erl_lint:
  erl_lint_SUITE: adjust failing test case
  Allow recursive types and check for undefined types

OTP-8421: ks/erl_lint

Hans Bolinder (the author/maintainer of qlc) prefers
for readability reasons to use length/1 in a guard
when it is known that the list is guaranteed to be
short, so the change suggested by tidier for line 875
of qlc_pt has not been included.