Fix httpd config option 'script_timeout'

This fixes the usage of the httpd configuration option 'script_timeout',
which got ignored before.

The documentation states that the value is in seconds, which was true
when using the Apache like configuration file, but not true when using
the proplist style configuration.
Remove ^L characters hidden randomly in the code. Not those used in text files as delimiters.

While working on a tool that processes Erlang code and testing it against this repo,
I found out about those little sneaky 0xff. I thought it may be of help to other
people build such tools to remove non-conforming-to-standard characters.
Add some more comments about what the test does

This changed the lines so the results now differ.
Fix a comment
Adopt a convention about unknown modules
Use the modern version of is_subtype
No reason for calls to unknown modules
Adopt a convention about unknown modules
Fix crash when using remote types in the tail of list types

Hans Bolider reported a dialyzer crash when using a remote type in
the tail position of a maybe_improper_list() declaration. A test
was created (by extending an existing module of the testsuite)
and erl_types was modified to expand the remote type and not pass
it unexpanded to subsequent phases in the processing.
Merge branch 'kostis/dialyzer_R16B02_fixes/OTP-11374' into maint

* kostis/dialyzer_R16B02_fixes/OTP-11374:
  Fix crash when using remote types in the tail of list types
  Adopt a convention about unknown modules
  No reason for calls to unknown modules
  Use the modern version of is_subtype
  Adopt a convention about unknown modules
  Fix a comment
  Add some more comments about what the test does
Merge branch 'fenollp/treewide_remove_unexpected_0xff/OTP-11323' into maint

* fenollp/treewide_remove_unexpected_0xff/OTP-11323:
  Remove ^L characters hidden randomly in the code. Not those used in text files as delimiters.