Bring back clang on Travis
No more resolvers in Japan :(
Merge branch 'master' of github.com:jedisct1/dnscrypt-proxy

* 'master' of github.com:jedisct1/dnscrypt-proxy:
  Bring back clang on Travis
Revert "Bring back clang on Travis"

This reverts commit 1eb7a00e971328418126920829b52ae4b278b340.
Remove unused function.
Revert "No more resolvers in Japan :("

This reverts commit ef06bdbb8b577b9acab221f9330b7cf37098adde.