Set key to lowercase in cmdsInfoCache.Get()

[WTIFS]

In function cmdInfo(name string), we use lower cmd name to find the cmdsInfo.

//name is lower case
func (c *Ring) cmdInfo(name string) *CommandInfo {
	cmdsInfo, err := c.cmdsInfoCache.Get()
	if err != nil {
		return nil
	}
	info := cmdsInfo[name]
	if info == nil {
		internal.Logger.Printf("info for cmd=%s not found", name)
	}
	return info
}

But for extensions like bloom filter, the "command" returns names with uppercase.

I think if we use lowercase name to find the cmdInfo, then we should turn cmd names to lower case when we fill the cmdsInfoCache.

[vmihailenco]

Thanks