When redirecting Pdb's stdout file object, the commands
that use this to write output don't call flush() on the
object. This leads to problem when setting the stdout
file object to a fileobject created from a socket with
the makefile() method.

My proposed solution to this problem is for the Pdb
class to contain a method for writing to fileobjects
which can be overridden by programmers if they wish to
write to sockets or other streams that require flush()ing.

I can work on this patch if people thinks its a good idea.

Thanks, Matt