Add enum34 dependency.
Add enum34 dependency.

bparafina/nfldb,nivertech/nfldb,bparafina/nfldb,codeaudit/nfldb,verdimrc/nfldb,BurntSushi/nfldb,nivertech/nfldb,BurntSushi/nfldb,verdimrc/nfldb,codeaudit/nfldb