Move ConfigModule and LocalTestConfig into RegistryConfig

This is the final preparatory step necessary in order to load and load
configuration from YAML in a static context and then provide it either via
Dagger (using ConfigModule) or through RegistryConfig's existing static
functions.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=143819983

java/google/registry/dns/writer/dnsupdate/DnsUpdateConfigModule.java

@@ -16,7 +16,7 @@ package google.registry.dns.writer.dnsupdate;
 
 import dagger.Module;
 import dagger.Provides;
-import google.registry.config.ConfigModule.Config;
+import google.registry.config.RegistryConfig.Config;
 import org.joda.time.Duration;
 
 /** Dagger module that provides DNS configuration settings. */