Makefile.release: bogus all target (#666)
Makefile.release: bogus all target (#666)

Make the default target do nothing and put the actual release under a
'release' target. Prevent accidentally committing unwanted commits to
the repo.

Tested with `make -f Makefile.release -n`.
miekg/coredns,yongtang/coredns,johnbelamaric/coredns,varyoo/coredns,jremond/coredns,ii/coredns,ii/coredns,chrisohaver/coredns,johnbelamaric/coredns,miekg/coredns,jremond/coredns,coredns/coredns