sasl: Add no_dot_erlang start script

Sometimes it is wanted to start erlang without loading the user dependent
.erlang file, for example in scripts and configure tests.
sasl: Add no_dot_erlang documentation and tests
Don't try to add the log_mf_h handler in sasl unless configured to do so.

The functions add_error_logger_mf/1 and delete_error_logger_mf/1 in sasl.erl
are designed to do nothing if the handler configuration as returned by
get_error_logger_mf/0 is 'undefined'. However, that function returns a
triple {undefined,undefined,undefined} when the error_logger_mf_*
configurations have not been set. This makes SASL always try to add the
log_mf_h handler on startup, passing 'undefined' for each of the Dir, MaxB
and MaxF parameters. The gen_event callback function log_mf_h:init/1 will
then crash with a function_clause error, causing the handler to be silently
removed again. This patch fixes the problem by making get_error_logger_mf/0
return the single atom 'undefined' as it is expected to do.
Fix confusing documentation about error handlers in SASL

The SASL documentation confusingly talks about a handler 'error_logger_mf_h'
which doesn't actually exist. The handler is named 'log_mf_h', and it and
all other error handlers used by SASL are part of stdlib, not SASL itself.
This patch makes the documentation clearer.
Merge branch 'dgud/sasl/no_dot_erlang_boot/OTP-8479' into maint

* dgud/sasl/no_dot_erlang_boot/OTP-8479:
  sasl: Add no_dot_erlang documentation and tests
  sasl: Add no_dot_erlang start script
Merge branch 'richcarl/fix-sasl-handler-docs' into maint

* richcarl/fix-sasl-handler-docs:
  Fix confusing documentation about error handlers in SASL

OTP-11507
Fix boot file generation for intermediate releases.

A previous refactoring messed up the paths used in the start.boot
file used in intermediate releases generated for emulator upgrades.
[sasl] Test bugfix in branch 'schlagert/fix_emulator_upgrades'

OTP-11529
Prepare release