FIX link in readme [ci skip]
FIX link in readme [ci skip]

Section for < 2.0 users contains a link with markdown syntax. Use proper
rdoc syntax instead.

ipmobiletech/Google-Maps-for-Rails,michael-gabenna/Google-Maps-for-Rails,ekdin/Google-Maps-for-Rails,michael-gabenna/Google-Maps-for-Rails,ipmobiletech/Google-Maps-for-Rails,oelmekki/Google-Maps-for-Rails,oelmekki/Google-Maps-for-Rails,ekdin/Google-Maps-for-Rails,apneadiving/Google-Maps-for-Rails,apneadiving/Google-Maps-for-Rails