Staking

[tonimateos]

As a LAOS staker I want a pallet to offer staking capabilities so that I am able to stake I am more than happy mimicking the staking pattern by Moonbeam, but making sure that the total supply remains constant, as detailed in our tokenomics

ACCEPTANCE:

• Using extrinsics, I can delegate any amount of stake above a set minimum to any collator I choose.
• Periodically (at the same pace as in Moonbeam) the rewards that the collator gets are distributed proportionally to stake amount, discounting commission
• The collator can use extrinsics to set the commission charged
• All rewards come from the CI account

References: https://apps.moonbeam.network/moonbeam/staking One account can select one single collator

[ghost]

The following sub-tasks are added: #308, #309, #310 and #311