Remove allowing txns with less than 150000000 in priority are always allowed
Remove allowing txns with less than 150000000 in priority are always allowed

This feature was intended to allow high priority txns to always propagate
however there are issues with this as highlighted in issue #125

1) This feature is a magic number which is not a good idea to begin with
2) txns that have been floating around without getting mined for long periods of
   time end up rising in priority and avoiding getting rate limited which the
   consequence that our mempools are filling up much faster with un-mineable txns.
3) This value can and does override the minlimitertxfee value at times which makes
   it confusing for users who see that the minlimitertxfee is not being honoured.

BitcoinUnlimited/BitcoinUnlimited,arruah/ensocoin,marlengit/BitcoinUnlimited,AllanDoensen/BitcoinUnlimited,marcusdiaz/BitcoinUnlimited,marlengit/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,krzysztofwos/BitcoinUnlimited,marlengit/hardfork_prototype_1_mvf-bu,Justaphf/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,AllanDoensen/BitcoinUnlimited,cddjr/BitcoinUnlimited,Bitcoin-com/BUcash,cddjr/BitcoinUnlimited,marlengit/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,BitcoinUnlimited/BitcoinUnlimited,arruah/ensocoin,krzysztofwos/BitcoinUnlimited,krzysztofwos/BitcoinUnlimited,marcusdiaz/BitcoinUnlimited,marlengit/BitcoinUnlimited,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,arruah/ensocoin,cddjr/BitcoinUnlimited,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,AllanDoensen/BitcoinUnlimited,Justaphf/BitcoinUnlimited,cddjr/BitcoinUnlimited,cddjr/BitcoinUnlimited,BTCfork/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,Bitcoin-com/BUcash,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,arruah/ensocoin,marcusdiaz/BitcoinUnlimited,Justaphf/BitcoinUnlimited,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,marcusdiaz/BitcoinUnlimited,AllanDoensen/BitcoinUnlimited,AllanDoensen/BitcoinUnlimited,BTCfork/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,krzysztofwos/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,marlengit/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,Bitcoin-com/BUcash,krzysztofwos/BitcoinUnlimited,Justaphf/BitcoinUnlimited,Bitcoin-com/BUcash,Justaphf/BitcoinUnlimited,arruah/ensocoin,arruah/ensocoin,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,krzysztofwos/BitcoinUnlimited,marlengit/BitcoinUnlimited,Bitcoin-com/BUcash,BTCfork/hardfork_prototype_1_mvf-bu,marcusdiaz/BitcoinUnlimited,marcusdiaz/BitcoinUnlimited,BTCfork/hardfork_prototype_1_mvf-bu,cddjr/BitcoinUnlimited,marlengit/hardfork_prototype_1_mvf-bu,marlengit/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,Justaphf/BitcoinUnlimited,marlengit/BitcoinUnlimited,Bitcoin-com/BUcash,AllanDoensen/BitcoinUnlimited