update Tk

Hi, 

I've updated Tk libraries on CVS. This update includes some important 
supports. And probably, the eventloop with threads has quicker response 
than before. Please try!

  * tkfont.rb:  Fix bugs on TkFont.init_widget_font for Tk8.x.
    
  * tkafter.rb: Add self to 1st argument of interval- and loop-proc
      TkAfter#current_interval returns an interval (sleep) time value
      TkAfter#current_args returns an array of arguments
      TkAfter#return_value returns a return value of last loop-proc
        e.g. 
           TkAfter.new(
             proc{|obj| 500 - obj.current_interval}, 10, 
             [proc{|obj| p obj.current_args}, 'proc', 1], 
             proc{|obj| p obj.current_args; ['return', 2]}, 
             [proc{|obj| 
                p obj.return_value
                p ['proc', obj.current_args[0].call(obj.return_value[1], 
                                                    obj.current_args[1])]}, 
              proc{|*args| args[0] + args[1]}, 1], 
             proc{p ['proc', 4]} ).start(100)
  
  * tk*.rb: Allow to use Symbols for parameters. 
      Allow new notation of constructor (also allow old notation). 
        e.g.
          TkFrame.new('classname'=>'User'){|base|
            pack
            f = TkFrame.new(base, :classname=>'ButtonFrame').pack
            TkButton.new(
               :parent     => f,
               :text       => 'Quit', 
               :command    => proc{exit}
            ).pack(
               :fill => :x, 
               :pady => 2
            )
          }
  
  * tkcanvas.rb: (TkcItem) Add 'coords' parameter to the canvas item
      constructor (for new notation of constructor).
        e.g.
          c = TkCanvas.new.pack
          l = TkcLine.new(c, :coords=>[[0,0], [100,100]])
  
  * tcltklib.c: New 'mainloop' and 'mainloop_watchdog'. 
      The priority of their event-loop can be controlled.
      They accept an optional argument. 
      If it false, they don't exit although the root widget is destroyed. 
      This function is sometimes useful, if it is used with 'restart'. 
      'mainloop' can't treat Thread#join/value in a callback routine. 
      (e.g. TkButton.new(:command=>proc{p Thread.new{button.invoke}.value}) )
      'mainloop_watchdog' can treat them, but watchdog thread is always running
      (so, a little heavier than 'mainloop').
      If the purpose of using Thread#join/value is to do something under some 
      safe-level, please use Proc object.
      (e.g. :command=>proc{$SAFE=1;proc{$SAFE=2;button.invoke}.call;p $SAFE})
    
  * tk.rb: Support functions of new 'mainloop' and 'mainloop_watchdog'.
  
  * tk.rb: (Tk.restart) Add 'app-name' paramater and 'use' parameter.
      'app-name' specifies the name and the resource class of the
      application. If 'app-name' is specified to 'xxx', the application
      class on the resource database is set to 'Xxx' and the application
      name is changed by the same rule of Tk.appname method.  'use'
      specifies the main window for embedding the root widget instead of
      generating a new window.
    
  * tk.rb: Add new parameter 'widgetname' to the widget constructor to
      support effective use of Resource Database.  For example, the
      resource 'Xxx*quit.text: QUIT' can set the text of the button
      generated by the following code.
        e.g. 
          Tk.restart('Xxx')
          TkButton.new(nil, 'widgetname'=>'quit', 'command'=>proc{exit}).pack
          Tk.mainloop
  
  * tk.rb: TkOption::get always returns a tainted string.
      Add TkOption::new_proc_class. 
      It generates a class to import procedures defined on the resource
      database. For example, there is a following resource file. 
        ----< resource-test >------------
        *CMD.foo: {|*args| p [$SAFE, :foo, args]}
        *CMD.XXX.bar: {|*args| p [$SAFE, :bar, args]}
        *Button.command: ruby {p self; p $SAFE; TkOption::CMD::XXX.bar(1,2,3)}
        ---------------------------------
      The following code is a sample of use of the resource file. 
        e.g. 
          require 'tk'
          TkOption.readfile 'resource-test'
          p TkOption.new_proc_class(:CMD, [:foo], 1)
          p TkOption.new_proc_class(:XXX, [:bar], 2, false, TkOption::CMD)
          TkButton.new(:text=>'test').pack
          Tk.mainloop
-- 
                                  Hidetoshi NAGAI ([e-mail])