[Etoys] [fix] PasteUpMorph shall not accept ScriptEditorMorph version 3

[Yoshiki Ohshima]

  Karl,

  Thank you for bunch of fixes.  There are some comments:

  * [FIX]ObjectsTool drag and drop

    This was a feature so that you *can* drop a newly instanciated
    object onto the tab to dismiss it.  Given that the screen
    resolution is rather large, the chance of accidental drop is
    relatively low.  Do you have strong feeling?

  * [fix] PasteUpMorph shall not accept ScriptEditorMorph (version 3)

    This was also a feature.  Think Takashi's Demon Castle tutorial.
    This one and the other one has upside and downside, and not
    entirely obvious whether to be included or not.

  * [FIX]Position of picked up tile morph

    This is also a feature but a new one (See the versions).  It has
    been always an issue that kids couldn't see the drop zone in the
    scriptor.  I think the current behavior is ok, although hardcoded offset
    may not be right.

  * [BUG]ScriptEditorMorph>>acceptDroppingMorph: aMorph event:	evt

    I'll take a look at it.

  * [ENH]BookMorph buttons more visible

    Ah, this looks good.  I'd take this^^;

Thank you again.  Not all may not get in, but that is how it works
for the code from the "team" member^^;  Of course, if somebody has
another rationale, I'm all ears.

-- Yoshiki