Log Message:
Update lang/erlang* to 20.1.

Some highlights for 20.1:

- crypto, public_key: Extend crypto and public_key functions sign and
  verify with:
  - support for RSASSA-PS padding for signatures and for saltlength
    setting
  - X9.31 RSA padding.
  - sha, sha224, sha256, sha384, and sha512 for dss signatures as
    mentioned in NIST SP 800-57 Part 1.
  - ripemd160 to be used for rsa signatures.

- A new tuple in crypto:supports/0 reports supported MAC algorithms.

- diameter:
  - Add service option decode_format to allow incoming messages to be
    decoded into maps instead of records.
  - Decode performance has been improved.
  - Add service/transport option avp_dictionaries to give better
    support for dictionaries only defining AVPs.

- erts: Upgraded the ERTS internal PCRE library from version 8.40 to
  version 8.41.

- erts, kernel, tools: Profiling with lock counting can now be fully
  toggled at runtime in the lock counting emulator (-emu_type lcnt).

- erts: The zlib module has been refactored and all its operations
  will now yield appropriately, allowing them to be used freely in
  concurrent applications.

- erts, tools: Add erlang:iolist_to_iovec/1, which converts an
  iolist() to an erlang:iovec(), which is suitable for use with
  enif_inspect_iovec().

- erts: Add new nif API functions for managing an I/O Queue.

- observer/crashdump_viewer:
  - Reading of crash dumps with many binaries is optimized.
  - A progress bar is shown when the detail view for a process is
    opened.
  - The cdv script now sets ERL_CRASH_DUMP_SECONDS=0 to avoid
    generating a new crash dump from the node running the Crashdump
    Viewer.

- observer: Add system statistics and limits to frontpage in observer.

- public_key, ssl**: Improved error propagation and reports

- ssh: A new option modify_algorithms is implemented. It enables
  specifying changes on the default algorithms list.

- tools/xref: The predefined Xref analysis locals_not_used now
  understands the -on_load() attribute and does not report unused
  functions.

- tools/fprof: When sampling multiple processes and analyzing with
  totals set to true, the output now sums together all caller and
  callee entries which concerns the same function.