The line counter becomes invalid, when the rules with linewrap are
used. This issue appears, because the parsing FSM does not rollback
the line counter after attempting such rule.
Unit tests for 'token' and 'tokens' are also added.

The line counter becomes invalid, when the rules with linewrap are
used. This issue appears, because the parsing FSM does not rollback
the line counter after attempting such rule.

The code related to the introduction of unicode_string() and
unicode_char() has been removed. The types char() and string() have
been extended to include Unicode characters.

In fact char() was changed some time ago; this commit is about
cleaning up the documentation and introduce better names for some
functions.

Expect modifications, additions and corrections.

There is a kludge in file_io_server and
erl_scan:continuation_location() that's not so pleasing.

This commit is a preparation for introducing location information
(filename/line number) in stacktraces in exceptions. Currently
a stack trace looks like:

  [{Mod1,Function1,Arity1},
   .
   .
   .
   {ModN,FunctionN,ArityN}]

Add a forth element to each tuple that can be used indication
the filename and line number of the source file:

  [{Mod1,Function1,Arity1,Location1},
   .
   .
   .
   {ModN,FunctionN,ArityN,LocationN}]

In this commit, the fourth element will just be an empty list,
and we will change all code that look at or manipulate stacktraces.

The formating of Yecc's error messages has been improved.
(Thanks to Joe Armstrong.)

* ks/cleanups:
  percept: Clean up as suggested by tidier
  percept: Modernize types and specs
  parsetools: Don't use 'try...of' when 'try' will do
  parsetools: Use %% for comments at the beginning of a line
  parsetools: Replace lists:keysearch/3 with lists:keyfind/3
  parsetools: Modernize types and specs
  parsetools: Replace TABs with spaces
  runtime_tools: Modernize specs
  sasl: Eliminate tuple used as fun
  sasl: Add missing modules to app file
  asn1: Clean up as suggested by tidier
  os_mon: Modernize types and specs
  wx: Clean up as suggested by tidier

OTP-8455  ks/cleanups