Covers & Performance Notes for the entire string choir; RC update for Annual Review

* NEW: _coverTemplate.ai for cover-page layout (use Preview mode in
Illustrator to expose blocks);
* removed page 2 marking from all the parts;
* bow-position markings in the string choir are level with measure
number indications whenever possible;
* corrected ord., s. p. and s. t. markings to be uniform throughout the
part;
* corrected all of the touch-fourth harmonic notation for whole notes
(as Finale aligns them to an invisible stem);
* corrected part names for Violin I/II A/B;