Allow specifying output streams.

Allow specifying output streams.

Allow starting the monitor application with one or more of stdin,
stdout and stderr redirected to a file or anything which can be
opened with CreateFile().

New registry values corresponding to CreateFile() arguments for
stdin (and analogously for stdout and stderr):

AppStdin: Path to open.
AppStdinShareMode: Sharing mode.
AppStdinCreationDisposition: Creation disposition.
AppStdinFlagsAndAtrributes: Flags and attributes.

All are optional.  If no path is given for a particular stream it
will not be redirected.  If a path is given but any of the other
values are omitted they will receive sensible defaults.