More edits for cohesion in the README.
More edits for cohesion in the README.

slai11/youtube-8m,slai11/youtube-8m,forwchen/yt8m,lidalei/youtube-8m,forwchen/yt8m,google/youtube-8m,slai11/youtube-8m,KangHsi/youtube-8m,coded5282/youtube-8m,KangHsi/youtube-8m,slai11/youtube-8m,mwoodson1/youtube-8m-competition,hxkk/u8m_test