[TxMt] Version control menu tweak

[Michael Sheets]

> One trick introduced by Michael Sheets is to prefix items we do not  
> want to be considered for a certain letter with a “thin  
> space” (unicode character.)

To be specific "narrow no-break space", which you can insert from   
the 'special characters' box under the edit menu. The Subversion  
bundle uses this to give Commit precedence over Checkout. Should be  
noted however that the menu system is pretty braindead; using this  
trick makes it impossible to get to from the keyboard as it only  
allows leading chars to jump to. (Unless of course you actually type  
the narrow no-break space) The arrow keys still work however, as  
would the number keys for the first few commands in the menu.