remove unnecessary kernel traits
remove unnecessary kernel traits

UsesSquaredDistance is unnecessary as smart complier can do the same
optimization.

Azizou/mlpack,theranger/mlpack,lezorich/mlpack,darcyliu/mlpack,trungda/mlpack,theranger/mlpack,BookChan/mlpack,chenmoshushi/mlpack,palashahuja/mlpack,erubboli/mlpack,darcyliu/mlpack,lezorich/mlpack,ersanliqiao/mlpack,theranger/mlpack,bmswgnp/mlpack,Azizou/mlpack,BookChan/mlpack,trungda/mlpack,chenmoshushi/mlpack,ajjl/mlpack,bmswgnp/mlpack,ajjl/mlpack,minhpqn/mlpack,chenmoshushi/mlpack,ranjan1990/mlpack,stereomatchingkiss/mlpack,minhpqn/mlpack,stereomatchingkiss/mlpack,ajjl/mlpack,datachand/mlpack,palashahuja/mlpack,ranjan1990/mlpack,ersanliqiao/mlpack,ranjan1990/mlpack,minhpqn/mlpack,palashahuja/mlpack,Azizou/mlpack,datachand/mlpack,darcyliu/mlpack,bmswgnp/mlpack,thirdwing/mlpack,stereomatchingkiss/mlpack,erubboli/mlpack,BookChan/mlpack,datachand/mlpack,trungda/mlpack,lezorich/mlpack,erubboli/mlpack,thirdwing/mlpack,ersanliqiao/mlpack,thirdwing/mlpack