* middleware/proxy: add spray keyword
When spray is used, the proxy will, when all backend are down, spray to
each target. When not used, default to the old defaults: max 1 failure
and no spray. These defaults are also used when forwarding queries to
another CoreDNS instance.
Update the README with the new keyword.
* typos
* Make MaxFail = 1 again
* more reversals
* Changed reference to Caddy over to CoreDNS
* Removing references to caddy
* Fixed misleading error message to reference coredns
* Cleaning up references to caddy
* Adding clean and deps targets
Muscle memory is resulting in "make clean" commands.
* Adding test target to makefile
* More "Caddy" cleanup
