add icon coloring scheme to show status of tx

genera:
red is invalid
purple is default (should not happen when everything runs well)

for simple send:
green is new (till 3 confirmations)
green/brown is less new (4-6 confirmations)
brown is mature (more than 6 confirmations)

for sell offer:
green is new
green/blue is partially accepted
blue is accepted
blue/brown is partially paid
brown is paid

for sell accept:
green is new
grey is expired
brown is paid