Added a one-time menu initialization function, and from there, I can call MN_propagateBigFontFlag, supporting an mf_bigfont that will set MENUITEM_BIGFONT on all items in the menu.

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2464 86ba831e-150c-0410-ab35-e06eaae15ed9
Rigorous reference counting for dynamic vertices is now required since they can be released at different times.

git-svn-id: http://mancubus.net/svn/hosted/eternity/trunk@2465 86ba831e-150c-0410-ab35-e06eaae15ed9