strace improvements

[Chris Faylor <cgf@cygnus.com>]

I felt ambitious today so I've taken the time to change cygwin's
strace interface.

I've gotten rid of the environment variable interface in favor of
control from an external program.  So, to get an strace dump you
now do something like:

	strace -m1 -o/tmp/strace.out ls

The strace program will grab OutputDebugString information (this is new)
from the child and send it to the file /tmp/strace.out.

Here are the current options:

Option		Description
  f		Strace all children
  m		Supply strace mask (1 is the default)
  o fn		Specify output filename (default stdout)
  t		Translate Win32 errors to text mode.

I haven't checked this in yet, nor have I checked it on Windows 95.
There is also a gotcha in that strace is currently a cygwin program.  I
don't think it has to be a cygwin program.  It was just easier to write
that way.

Does this sound like the correct way to go with this?

-chris