Support more parenthesized score elements

If am not mistaken, currently MS only supports parenthesized accidentals and note heads.

It would be useful to support more parenthesized score elements; currently it is necessary to add a text element with the parentheses, size it properly and position it properly, which is time consuming and hard to make consistent.

Elements to support could be:

*) Clefs
*) Key signature (first time it is used)
*) Time signatures
*) Articulations and Ornaments (the most important)

Other elements, being textual, can be more simply edited manually to included the parentheses, requiring no additional support, namely: dynamics, fingerings, repeats, tempos.

The use for this is in critical editions to indicate an editorially added element.

Thanks, M.