Add very basic (possibly temporary) Provider configs

config.go

@@ -27,6 +27,7 @@ type Config struct {
 	Swarm     SwarmConfig
 	Pubsub    PubsubConfig
 
+	Provider     Provider
 	Reprovider   Reprovider
 	Experimental Experiments
 }

provider.go

@@ -0,0 +1,5 @@
+package config
+
+type Provider struct {
+	Strategy string // Which keys to announce
+}