Make lamports per signature dynamic

[michaelh-laine]

Is your feature request related to a problem? Please describe. Solana will in the near future introduce more complex transaction fee pricing and there won't be a singular "lamports per signature" value. Transactions will be priced more accurately based on the compute units they consume.

Describe the solution you'd like Octane would need to pull the fees from the chain for each transaction as it isn't reliable to assume a fee in advance. This is not an issue right now but for future proofing this is important.