* dnsfilter: use golibs/cache

+ config: add cache size settings
+ config: add cache_time setting

home/config.go

@@ -211,6 +211,12 @@ func initConfig() {
 		// also change the default config
 		config.DNS.UpstreamDNS = defaultDNS
 	}
+
+	config.DNS.CacheSize = 4 * 1024 * 1024
+	config.DNS.SafeBrowsingCacheSize = 1 * 1024 * 1024
+	config.DNS.SafeSearchCacheSize = 1 * 1024 * 1024
+	config.DNS.ParentalCacheSize = 1 * 1024 * 1024
+	config.DNS.CacheTime = 30
 }
 
 // getConfigFilename returns path to the current config file