compiler: Conform returned errors to the documented format

ErrorInfo is documented to be:

  {ErrorLine,Module,ErrorDescriptor}

but for some errors with line numbers it would look like:

  {Module,ErrorDescriptor}

Ensure that all ErrorInfo tuples have three elements. Use 'none'
instead of a line number:

  {none,Module,ErrorDescriptor}

There already are errors that return 'none' when no line number is
available, but that convention was not documented. Mention it in the
documentation.

Also make sure that the compiler will not print 'none' as a line
number in error messages (if the 'report_errors' option is given) as
that looks stupid. That is, when attempting to compile a non-existing
module, the error message should be:

  non-existing.erl: no such file or directory

and not:

  non-existing.erl:none: no such file or directory
Change encoding of troublesome notes.xml files to utf-8

Most notes.xml files will be updated in every release and cause
the kind of the problems described in the previous commit.
Merge branch 'maint'

* maint:
  compiler: Conform returned errors to the documented format
Merge branch 'bjorn/xml-encoding-fix/OTP-11310' into maint

* bjorn/xml-encoding-fix/OTP-11310:
  Change encoding of troublesome notes.xml files to utf-8
  Convert some notes.xml files from latin-1 to utf-8
Merge branch 'maint'

* maint:
  Change encoding of troublesome notes.xml files to utf-8
  Convert some notes.xml files from latin-1 to utf-8
core_lint: Correct the type error() to conform to the code

Commit 60984ade updated the code, but not the type spec.

Noticed-by: Kostis Sagonas
Merge branch 'maint'

* maint:
  core_lint: Correct the type error() to conform to the code