Clean up Base58 implementation and improve its documentation.
Clean up Base58 implementation and improve its documentation.

HashEngineering/dashj,bitcoinj/bitcoinj,framewr/bitcoinj,patricklodder/bitcoinj,marctrem/bitcoinj,langerhans/bitcoinj-alice-hd,nikileshsa/bitcoinj,patricklodder/bitcoinj,VishalRao/bitcoinj,HashEngineering/dashj,kurtwalker/bitcoinj,MrDunne/bitcoinj,peterdettman/bitcoinj,patricklodder/bitcoinj,langerhans/dogecoinj-new,HashEngineering/dashj,jdojff/bitcoinj,HashEngineering/darkcoinj,you21979/bitcoinj,blockchain/bitcoinj,HashEngineering/groestlcoinj,dcw312/bitcoinj,kurtwalker/bitcoinj,HashEngineering/groestlcoinj,jdojff/bitcoinj,strawpay/bitcoinj,yenliangl/bitcoinj,you21979/bitcoinj,tangyves/bitcoinj,yenliangl/bitcoinj,you21979/bitcoinj,oscarguindzberg/bitcoinj,natzei/bitcoinj,tjth/bitcoinj-lotterycoin,peterdettman/bitcoinj,tjth/bitcoinj-lotterycoin,peacekeeper/bitcoinj,rnicoll/bitcoinj,GroestlCoin/groestlcoinj,jdojff/bitcoinj,janko33bd/bitcoinj,therightwaystudio/fork_bitcoinj,schildbach/bitcoinj,Enigmachine/btcjwork2,designsters/android-fork-bitcoinj,rootstock/bitcoinj,kmels/bitcoinj,natzei/bitcoinj,bitsquare/bitcoinj,GroestlCoin/groestlcoinj,dexX7/bitcoinj,szdx/bitcoinj,GroestlCoin/groestlcoinj,tangyves/bitcoinj,HashEngineering/darkcoinj,janko33bd/bitcoinj,HashEngineering/darkcoinj,bitcoinj/bitcoinj,tangyves/bitcoinj,greenaddress/bitcoinj,HashEngineering/groestlcoinj,tjth/bitcoinj-lotterycoin,kurtwalker/bitcoinj,oscarguindzberg/bitcoinj,schildbach/bitcoinj,cpacia/bitcoinj,cpacia/bitcoinj,paulminer/bitcoinj,cpacia/bitcoinj,dalbelap/bitcoinj,imzhuli/bitcoinj,HashEngineering/dashj,kmels/bitcoinj