Fix log output of the version string. (#910)
Fix log output of the version string. (#910)

Split version string into two, before:
```
2017/08/12 19:43:08 [INFO] CoreDNS-010
linux/amd64, go1.8.3, a6d2d7b5
CoreDNS-010
linux/amd64, go1.8.3, a6d2d7b5
```
After:
```
root@9bd51ffc39aa:/go/src/github.com/coredns/coredns# ./coredns
.:53
2017/08/12 19:12:59 [INFO] CoreDNS-010
2017/08/12 19:12:59 [INFO] linux/amd64, go1.8, a6d2d7b
CoreDNS-010
linux/amd64, go1.8, a6d2d7b
```

Signed-off-by: Yong Tang <765086fe2e0c1f980161f127fec596800f327f62@outlook.com>
coredns/coredns,chrisohaver/coredns,ii/coredns,jremond/coredns,johnbelamaric/coredns,ii/coredns,miekg/coredns,yongtang/coredns,jremond/coredns,johnbelamaric/coredns,miekg/coredns