Add Basic Redis HLL module

Add a base class for tracking purpose Gitlab::UsageData::BaseHLL

• Here have the the expiry values 29 days
• Add some other common parts
• Add a base key format, with a weekly key(I'm not 100% sure about weekly keys, as this myght couse us to miss some data if the weeks are not full when we build the usage ping, unless we explicit get the count for last 4 full weeks)

Ex: if we send usage ping Wendesday (current week is not complete) so we would need to look for the 4 complete weeks before, expiry time should also increase in this case