Testing was conducted only using explicit parameters, and using
testsuite. However, when the parameters are not explicitly set in JSON
config, it seems that `c.MaxUploadSize` will contain `RandRangeConfig {
From: 0, To: 0 }` instead of `nil`, which breaks upload entirely.
* maxUploadSize and maxConcurrentUploads can now be ranges on the client
* maxUploadSize is now enforced on the server
* the default of maxUploadSize is 2MB on the server, and 1MB on the client
* the default of maxConcurrentUploads is 200 on the server, and 100 on the client
* ranges on the server are treated as a single number. if server is configured as `"1-2"`, server will enforce `2`
* querystrings in `path` are now handled correctly
