Making mach quiet

[Ville Skyttä]

Any objections against applying the attached patch?  It makes mach
quieter and gets rid of the spinner crap that ends up in current build
logs.  

This junk appears to make browsers (at least Firefox) not to open the
build log but to ask for an app to handle it even though it's sent as
text/plain.  For example:
http://extras64.linux.duke.edu/failed/development/uudeview/0.5.20-6/x86_6...