Add redis driver

Signed-off-by: Asai Neko <sugar@sne.moe>

config/types.go

@@ -3,6 +3,7 @@ package config
 type config struct {
 	Server   server   `yaml:"server"`
 	Database database `yaml:"database"`
+	Cache    cache    `yaml:"cache"`
 	Email    email    `yaml:"email"`
 	Secrets  secrets  `yaml:"secrets"`
 	TTL      ttl      `yaml:"ttl"`
@@ -23,6 +24,14 @@ type database struct {
 	Password string `yaml:"password"`
 }
 
+type cache struct {
+	Hosts    []string `yaml:"hosts"`
+	Master   string   `yaml:"master"`
+	Username string   `yaml:"username"`
+	Password string   `yaml:"passowrd"`
+	DB       int      `yaml:"db"`
+}
+
 type email struct {
 	ResendApiKey string `yaml:"resend_api_key"`
 	From         string `yaml:"from"`