* optional old-style editing mode for macros with a parameter list.

* optional old-style editing mode for macros with a parameter list.
* combobox in the preferences dialog to choose the macro editing mode of choice.

The reason for the three choices (inline box, inline without box,
list) is that it seems that there are at least these three groups of
people, and each of them is very strong about their opinion what that
the best mode is. So here there are all of them, pick your favourite.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@22670 a592a061-630c-0410-9148-cb99ea01b6c8