Issue Releated with Checksum on install-tl.zip

[Karl Berry]

    Thinking of the idea of verifying the checksum per mirror is nice
    but sometimes it did happen to me that both redirected to different
    mirror and caused problem. 

Norbert went to some trouble with tlmgr/install-tl so that once a ctan
mirror is chosen, the same mirror gets used for further downloads in a
given run. Letting a different ctan mirror be chosen for different files
is a recipe for failure.

Also, it would not be good for every tinytex user (or chocolatewhatever
user) to be downloading install-tl.zip (or anything else) directly from
tug.org. This is why ctan exists, to avoid overburdening any single
server. I'm not sure if this is what you are now thinking of doing, but
it kind of sounded like it, so thought I'd mention. --best, karl.