[feat]: Implement better bounty relay evaluation.

[jsanmigimeno]

Finish the implementation (jsanmi/pricing):

• Take into account wallet configuration (gas price adjustment)
• Take into account how gas is computed in different chains (depends on #25)
• Make sure the verification logic is taken into account on the cost estimation.
• Decide whether to make use of the evaluation class or otherwise.
• Implement 'strong incentives'

[jsanmigimeno]

Logic implemented via #29. This logic must be tested in testnet.