v0.4
  Bugfixes
  - bugfix for MacOSX: added missing libraries in the link phase.
  - in type check, when doing type inference, a bug appeared when then head of
    the clause has the wrong type (for example, when a chr constraint
    was declared of type pred instead of chr_constraint) instead of
    correctly reporting the error.

  Speed improvements
  - uses backtracking to reinitialize solvers in between type checking of two 
    connex parts.
  - added some checks to avoid propagating type constraints that dont change 
    anything.
  - removed intermediate type variables in type checking.

  Minor updates
  - added an error when declaring a type constructor twice but with a 
    different number of arguments.
  - clauses for the predicate tclp__files:file_search_path/2 can be added so 
    tclp can find module of the form some(thing) (same use as
    user:file_search_path/2).
  - error messages should be in one line now
  - added keyword `subtype' as an alias for `order'

  Type libraries updates

  Command line options
  - Removed some (not very useful) switches
v0.3b
  - bugfix in type inference when heuristics fail
v0.3
  - created a tclp subdir in the src directory
  - now tclp executable uses the tclp library
  - auto location of the tclp directory: one doesn't need to specify were are
    the standard type libraries
  - the strong typing of equality is now available only via an option
    (--strong_eq), since it does not corresponds to the true type discipline
     of tclp
  - fixed a bug in type inference (was too restrictive and didn'nt
    provided the term x ... x term -> pred type by default)
  - added the manual

v0.2.99h (was an experimental version)
  - changed the typing of equality: now =/2 is typed in a way such that both 
    of its arguments must have the same type. Before, they were asked to 
    have a common supertype. This provides a stricter type checking and a 
    more precise type inference.

v0.2.99g
  - fixed bug in the type constraint solver that could have make it loop.
  - added library of types for GNU Prolog
  - now provides a way to install tclp as a library for sicstus.
  - the handling of ',' and 'op' has been moved to the corelib.typ files

v0.2.99f
  - added the possibility to change the type of predicates defined by a clause:
    ex: +: defines a 'fd_constraint' and not a 'pred'.
    - changed type libraries to use this
    - added tclp__define_clause_op(Operator,TypeOfPredicate)
    - Heads in tclp__define_clause(Clause,Location,Heads,Bodies(,Conditions)) 
      are now triplets (Head - HeadLocation - HeadType)
  - removed computing of connex parts when doing type check only
  - added connex component timing when -v actions -v timing are enabled
  - implemented a heuristic for choosing the next overloaded symbol to 
    disambiguate
