a storage miner should be provided with commands to set the minimum and maximum piece size they're willing to accept in a storage deal

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Request

We should introduce a CLI command which allows a storage miner to configure the minimum and maximum piece sizes for which they are willing to accept storage deal proposals.

Acceptance critiera

1. An operator of a lotus storage miner should be provided with commands which allows them to set their minimum and maximum piece size.
2. A lotus storage miner which receives a storage deal proposal for a piece with a size which is below the minimum that it has specified should automatically reject that proposal.
3. A lotus storage miner which receives a storage deal proposal for a piece with a size which is above the maximum that is has specified should automatically reject that proposal.
4. The storage client should receive some feedback (perhaps through the lotus client list-deals command) that their deal proposal was rejected and some text which indicates that their piece was either too large or small.