Equip the wallet with an "optimum fee guesser"

[rico666]

The mobile wallet should suggest the optimum fee for a transaction to make sure - with sufficient confidence - that transaction gets incorporated in the next block (or into one of the next blocks) - certainly before the tx timeout runs out.

Having a fixed tx fee is problematic, because it may be too low in high traffic conditions and too high in low traffic times.

The guesser could look at the average fill of the past 10 blocks and use the median of transactions * FEE_QUANT for a good approximation of the optimum fee.

[rico666]

Wait for https://github.com/PoC-Consortium/burstcoin/issues/360 as it will simplify the job greatly.

[rico666]

And done: https://github.com/PoC-Consortium/burstcoin/pull/361

Robust implementation would be:

• check if backend wallet offers suggestFee API
• if no, use some fixed amount default
• if yes get the cheap, standard, priority and offer them as presets

(the user can edit the fee always)