#325 XMLPlugin: Reformat text between tags

[Alan Ezust]

jEdit has a built-in reformat paragraph which is quite useless in XML mode, since
the concept of a paragraph is a little different there.

For docbook and HTML files it would be nice if I had an action from the XML plugin, that lets me reformat the text between the corresponding start and end tags that surround my cursor, and remove all linewraps between if we have softwrap, or add appropriate linewraps if we have hard wrap.