Add Coveralls badge to README.md, this closes apache/incubator-pirk#47
Add Coveralls badge to README.md, this closes apache/incubator-pirk#47

tellison/incubator-pirk,jacobwil/incubator-pirk,smarthi/incubator-pirk,ellisonanne/incubator-pirk,wraydulany/incubator-pirk