cosmetic tweaks to README.md file
cosmetic tweaks to README.md file

reiver/go-porterstemmer,kiteco/go-porterstemmer,Shugyousha/go-porterstemmer,sajari/go-porterstemmer,blevesearch/go-porterstemmer,jmptrader/go-porterstemmer,cuevasclemente/go-porterstemmer