It seem that pip has updated its verbose output to say "Downloading
$filename" rather than "Downloading from url $URL". We need to update
our wheel mirror processing to handle this change so that it can
properly remove any pypi hosted wheels before publishing to our wheel
mirrors. Make it more liberal so we match pretty much any line with
"Downloading" and then eventually something which looks like a whl
file, just in case they keep fiddling with it.
Change-Id: I7965f296cdb1241c96293edd68e84e1d3d78b331
b42840391a