Add version badge to README.rst
Add version badge to README.rst

scholarly/pynacl,pyca/pynacl,reaperhulk/pynacl,ucoin-io/cutecoin,pyca/pynacl,scholarly/pynacl,JackWink/pynacl,pyca/pynacl,alex/pynacl,xueyumusic/pynacl,Insoleet/cutecoin,alex/pynacl,xueyumusic/pynacl,reaperhulk/pynacl,xueyumusic/pynacl,reaperhulk/pynacl,reaperhulk/pynacl,alex/pynacl,pyca/pynacl,hoffmabc/pynacl,scholarly/pynacl,ucoin-io/cutecoin,alex/pynacl,scholarly/pynacl,lmctv/pynacl,xueyumusic/pynacl,ucoin-bot/cutecoin,pyca/pynacl,hoffmabc/pynacl,hoffmabc/pynacl,lmctv/pynacl,JackWink/pynacl,JackWink/pynacl,ucoin-io/cutecoin,lmctv/pynacl,lmctv/pynacl,reaperhulk/pynacl,lmctv/pynacl,JackWink/pynacl