swift234

implement AST and sema support for methods.  The example method in the
testcase now AST's to:

   (methdecl 'print2' type='(this : rect) -> (os : ostream) -> ()'
      (closure_expr type='(this : rect) -> (os : ostream) -> ()'
        (closure_expr type='(os : ostream) -> ()'
          (brace_expr type='()'
            (apply_expr type='int'
              (declref_expr type='(r : rect) -> int' decl=area)
              (tuple_expr type='(r : rect)'
                (declref_expr type='rect' decl=this)))))))

which seems right.  Some cleanups are pending.



Swift SVN r416