[CM] eval aborting

[Heinrich Taube]

i have a version of grace that uses S7's new 'interrupt scheme'  
feature that  stop infinite loops without using signals. to abort the  
current eval taking place use the Eval>Interrupt Scheme  menu item  
(ill add a Keyboard shortcut for this too). it seems to work, would  
appreciate testing.  note that if an infinite loop involves printing  
to the Console window the app may still crash due to the flood of  
asynchronous print messages hammering the underlying  text buffer.  
this is not a s7 issue (or even a Grace issue) -- im going to try to  
reimplement the Console window without a text buffer to solve this  
problem and to make printing faster.

http://camil.music.uiuc.edu/software/grace/Grace-3.7.1-beta2-osx.zip