Move withdraw address validate of coin to background job.
submit market order via api
fix number precision of origin volume
add migration task to set order locked attribute
fix order spec
rename sum_limit to locked in matching engine
fix executor validation
fix order loading on engine initialization
better trade logging
cancel market order if its locked fund run out
Compute used funds by matching engine

It's always matching engine's responsibility to calcualte. Trade
executor should only execute, with no questions, command and numbers
send from matching engine. Trade executor should not calculate again.
expose trade funds
refactor Order#avg_price
fix orders api spec
estimate the funds required by market order
Rename coin_deposits to payment_transaction
Move walletnotify coin deposit to background job
Update requirements.md
send order cancel message to order processor
order processor cancel order