Include the number of messages
xattrs can have punctuation
Disable gratuitous logging
Make the page size 10, which seems to work in production.
Make the maximum number of connections 50
Correctly set the reply error if an API method fails
Better error handling in the path resolution API, as well as better
clean-up (fixes race conditions and use-after-free problems).
Try timed-out connections again
Set default retry attempts to nonzero
Better validation for cancellations and download set detachment
Retry publish on EAGAIN.  Also, fix request offset calculation when
starting requests, and use the correct number of network contexts to
check when determining how many contexts are still running.
Better debugging; cache miss isn't an error.
Temporarily disable error checks on thread creation until we know how to
handle it better.
Add "quickstart" command-line option to skip publishing data.
TODO: set a default driver in quickstart mode.