Add a method to query the character attributes for an entire selection

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carlos.lucasius@canada 1998-04-06:
RFE from Corel (licensee) for JFC1.1 using JDK1.1.4 on WINNT4.0.
Corel: "Important for our product."

As it is, there's a method to get the attributes at the current caret
location (getCharacterRunAttributes). This does a great job of tracking
the attributes and works great when there is no selection. What we'd
really like to see added is a method to query the attributes for an entire
selection... Something like:
getSelectionCharacterAttributes and getSelectionParagraphAttributes.

This would also require that attributes have either a definite or
special value indicating that it is present, but not shared by the
entire selection. In other words, if you've selected some text where
some is bold and some is not and you query the selection's attribute
set for the StyleConstants.Bold attribute, the return value could
be one of the following:

    Boolean.TRUE or Boolean.FALSE: this means ALL the selected text is
bold or not bold
...or some other defined object... for example...
    StyleContants.Partial: this means that some, but not all the
selected text is bold.

It now becomes more tedious to track the attribute run. An
AttributeTracker class like the one in StyledEditorKit would have to
make a much more complicated decision about when the current set of
attributes has changed. It would no longer be able to just take the
attributes at the caret location but would have to cycle through the
attribute sets of all currently selected character/paragraph elements
and combine their attributes. In combining those attributes, it would
also have to determine if attributes are shared by some but not all of
the selection and set their values accordingly.

Another issue this creates is what to do when different types of content,
with different types of attributes are all selected... ie: text, images,
links, etc...