Bug#353556: #353556: choose-mirror: should check that architecture is supported by mirror

[Tollef Fog Heen <tfheen@err.no>]

* Frans Pop 

| The attached patch will check if the architecture is supported by reading 
| the index.html file for the binary-$arch directory and checking if there 
| is a reference to a Packages.gz file in that. If the arch is not 
| supported, the wget will return 404 and the check will fail.

Ew.  So we don't support mirrors which don't provide indices?  Why not
just do a HEAD request instead?  (Yes, wget doesn't support it yet,
but that would be a much nicer way to do it and should be easy enough
to fix.)

-- 
Tollef Fog Heen                                                        ,''`.
UNIX is user friendly, it's just picky about who its friends are      : :' :
                                                                      `. `' 
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