* Rename middleware to plugin
first pass; mostly used 'sed', few spots where I manually changed
text.
This still builds a coredns binary.
* fmt error
* Rename AddMiddleware to AddPlugin
* Readd AddMiddleware to remain backwards compat
When looking for a name in tree, return wether we got to a longer one -
if so we had an ent. Add tests + dnssec tests and refactor the tests as
well a bit.