Discretize fee levels (follow-up 3314b3a). Fixes #1753

lib/bitcoin.py

@@ -37,6 +37,7 @@ import aes
 
 ################################## transactions
 
+FEE_STEP = 10000
 RECOMMENDED_FEE = 50000
 COINBASE_MATURITY = 100
 COIN = 100000000

lib/util.py

@@ -36,6 +36,7 @@ import threading
 from i18n import _
 
 base_units = {'BTC':8, 'mBTC':5, 'uBTC':2}
+fee_levels = [_('Very low'), _('Low'), _('Normal'), _('High'), _('Very high')]
 
 def normalize_version(v):
     return [int(x) for x in re.sub(r'(\.0+)*$','', v).split(".")]