Add out-of-order sample support to the TSDB

[codesome]

This implementation is based on this design doc:
https://docs.google.com/document/d/1Kppm7qL9C-BJB1j6yb6-9ObG3AbdZnFUBYPNNWwDBYM/edit?usp=sharing

This commit adds support to accept out-of-order ("OOO") sample into the TSDB
up to a configurable time allowance. If OOO is enabled, overlapping querying
are automatically enabled.

[codesome]

This replaces #268. Somehow having a single commit while manually adding co-authors removes the CLA requirement from the co-authors. (See 268, CLA fails because Dieter hasn't signed, but it does not fail here).

[codesome]

We can consider merging this after #270 is merged and synced in this PR.

[jesusvazquez]

Lets get the OOOAllowance changes and the OOO WBL dir rename into this PR.

[jesusvazquez]

I did take a look at some of the TODO comments that we can get rid of. Can you take a look at the comments @codesome?

[codesome]

Opened #273 for TODOs

[jesusvazquez]

Preemptively approving knowing that you will rebase this PR with the changes from #273

Let's goooo 🎉 🎉 🎉 🎉

[pstibrany]

This PR changes ChunkReader interface in a way that's incompatible with usage in Thanos and Mimir. We could fix Mimir, but unless you plan to vendor mimir-prometheus in Thanos, it needs to be reverted :(

[nwpuCfy]

This PR changes ChunkReader interface in a way that's incompatible with usage in Thanos and Mimir. We could fix Mimir, but unless you plan to vendor mimir-prometheus in Thanos, it needs to be reverted :(

Did this mean TSDB that supports out of order data is not compatible with thanos? So I can't use it in cortex v1.11 that supports obs storage?

[codesome]

@nwpuCfy that comment was about code interface and not the data format. Thanos has switched to the new interface I think. And they use prometheus/prometheus, and not grafana/mimir-prometheus.

[jesusvazquez]

@nwpuCfy As @codesome pointed out, thanos is now vendoring prometheus/prometheus were we ported the changes you see in this PR so there should not be any problems 👍 Use prometheus/prometheus as your reference for the official state of out-of-order support.

[nwpuCfy]

@nwpuCfy As @codesome pointed out, thanos is now vendoring prometheus/prometheus were we ported the changes you see in this PR so there should not be any problems 👍 Use prometheus/prometheus as your reference for the official state of out-of-order support.
ok, thanks for reply

[nwpuCfy]

@nwpuCfy that comment was about code interface and not the data format. Thanos has switched to the new interface I think. And they use prometheus/prometheus, and not grafana/mimir-prometheus.

thanks for reply