[Tilesathome] Rate limiting on upload page

[Nic Roets]

404 idea: One simple idea is to create a simple little program that
runs under "nice". Once that command gets CPU time it creates a
simlink that points to the actual upload PHP handler. The PHP handler
then deletes the simlink when it starts. This will cause other
uploaders to get 404 errors until the CPU is idle enough for the niced
program to run.

Another solution is to have a "serverLoad.php" script that the clients
must check.

Another solution is just to ask rjm, damian and the other "bot" owners
nicely. And if they don't listen, change the request interface to
verify the presence of a human with a "puzzle" question.