generic tx fees

[omritoptix]

txfees module will have the follwing logic:

• will replace original cosmos-sdk's DeductFee handler, with 2 handler - MempoolCheck and DeductFee

• Will swap and burn all tokens in it's balance on epoch start

• Will manage accepted fees by hooking to the pool creation hook

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• ante handler to accept fees
• pool creation hook to facilitate the allowed denoms
• swap and burn on epoch
• add param to epoch identifier and burn/distribute

[mtsitrin]

Few notes regarding the difference between our/osmosis/ethermint/cosmos implementations:

logic separated into two components

1. mempoolChecker - checks that the fee is sufficient
2. feeDeducter - deducts the supplied fee

In Cosmos:

• mempool fees checked on ctx.IsCheckTx() only
• all fees deducted sent for Distribution

In Ethermint:

• same dedcutFee as in cosmos - all fees sent for Distribution
• uses custom DynamicFeeChecker following the EIP-1559

In Osmosis:

• custom mempool checker
• • runs always, not only on checkTx
• • have additional gas checks: Add separate min gas price option for txes with high gas wanted osmosis-labs/osmosis#777

For dymension:

• mempool check on checkTx() with no additional gas limit checks
• FeeDeducter similar to osmosis - DYM goes to distribution, non-DYM to txfee to be burned

@omritoptix @shaolin-flow WDYT