Prefer immutable seq's
Prefer immutable seq's

Co-Authored-by: Dale Wijnand <b856135c55286cebfee659b9877b42230aab1753@gmail.com>

benmccann/playframework,mkurz/playframework,benmccann/playframework,wegtam/playframework,mkurz/playframework,wegtam/playframework,benmccann/playframework,mkurz/playframework,playframework/playframework,marcospereira/playframework,benmccann/playframework,playframework/playframework,marcospereira/playframework,wegtam/playframework,marcospereira/playframework,mkurz/playframework,wegtam/playframework,marcospereira/playframework,playframework/playframework