update to spectator 0.57.1 (#648)
update to spectator 0.57.1 (#648)

Fixes issues when running on jdk9:

```
Cause: ba0f46c713d5122c4ac5a9acbcf7810d3a490c33@7d3cb5af)
   at java.base/java.lang.invoke.MemberName.makeAccessException(MemberName.java:914)
   at java.base/java.lang.invoke.MethodHandles$Lookup.checkAccess(MethodHandles.java:2193)
   at java.base/java.lang.invoke.MethodHandles$Lookup.checkMethod(MethodHandles.java:2133)
   at java.base/java.lang.invoke.MethodHandles$Lookup.getDirectMethodCommon(MethodHandles.java:2282)
   at java.base/java.lang.invoke.MethodHandles$Lookup.getDirectMethodNoSecurityManager(MethodHandles.java:2276)
   at java.base/java.lang.invoke.MethodHandles$Lookup.unreflectSpecial(MethodHandles.java:1800)
   at com.netflix.spectator.impl.Config.lambda$createProxy$3(Config.java:131)
```
brharrington/atlas,copperlight/atlas,copperlight/atlas,brharrington/atlas,brharrington/atlas,copperlight/atlas,Netflix/atlas,Netflix/atlas,Netflix/atlas