build: add --mode option to configure.py
build: add --mode option to configure.py

By default both debug and release binaries are built. It makes the
build take longer than necessary, it's rarely needed to have both
versions during development. To build only one of them, do:

  $ ./configure --mode debug
  $ ninja

senseb/scylla,phonkee/scylla,bowlofstew/scylla,kjniemi/scylla,bzero/seastar,stamhe/seastar,eklitzke/scylla,kangkot/scylla,rluta/scylla,capturePointer/scylla,guiquanz/scylla,anzihenry/seastar,stamhe/scylla,senseb/scylla,justintung/scylla,sjperkins/seastar,rentongzhang/scylla,cloudius-systems/seastar,wildinto/scylla,raphaelsc/seastar,hongliangzhao/seastar,stamhe/scylla,koolhazz/seastar,kjniemi/scylla,aruanruan/scylla,anzihenry/seastar,aruanruan/scylla,rentongzhang/scylla,guiquanz/scylla,sjperkins/seastar,ducthangho/imdb,avikivity/seastar,scylladb/seastar,guiquanz/scylla,bowlofstew/seastar,scylladb/scylla-seastar,justintung/scylla,syuu1228/seastar,scylladb/seastar,scylladb/scylla,stamhe/seastar,bowlofstew/seastar,wildinto/seastar,koolhazz/seastar,eklitzke/scylla,dreamsxin/seastar,rluta/scylla,dwdm/scylla,kjniemi/seastar,scylladb/scylla-seastar,tempbottle/scylla,raphaelsc/seastar,bowlofstew/scylla,kangkot/scylla,acbellini/scylla,shaunstanislaus/scylla,leejir/seastar,dwdm/seastar,tempbottle/scylla,cloudius-systems/seastar,shyamalschandra/seastar,gwicke/scylla,wildinto/scylla,justintung/scylla,flashbuckets/seastar,tempbottle/seastar,bzero/seastar,norcimo5/seastar,anzihenry/seastar,chunshengster/seastar,syuu1228/seastar,shaunstanislaus/scylla,xtao/seastar,joerg84/seastar,linearregression/seastar,acbellini/seastar,mixja/seastar,avikivity/seastar,bzero/seastar,wildinto/seastar,mixja/seastar,slivne/seastar,printedheart/seastar,flashbuckets/seastar,bowlofstew/seastar,shyamalschandra/seastar,flashbuckets/seastar,jonathanleang/seastar,wildinto/scylla,acbellini/scylla,printedheart/seastar,kangkot/scylla,sjperkins/seastar,syuu1228/seastar,gwicke/scylla,xtao/seastar,scylladb/scylla,raphaelsc/scylla,acbellini/scylla,respu/scylla,stamhe/scylla,hongliangzhao/seastar,linearregression/scylla,avikivity/scylla,glommer/scylla,phonkee/scylla,phonkee/scylla,capturePointer/scylla,senseb/scylla,hongliangzhao/seastar,asias/scylla,leejir/seastar,koolhazz/seastar,acbellini/seastar,asias/scylla,dwdm/scylla,avikivity/scylla,victorbriz/scylla,dreamsxin/seastar,tempbottle/seastar,avikivity/scylla,leejir/seastar,chunshengster/seastar,tempbottle/scylla,scylladb/scylla,acbellini/seastar,jonathanleang/seastar,dwdm/scylla,capturePointer/scylla,duarten/scylla,duarten/scylla,kjniemi/scylla,linearregression/seastar,raphaelsc/scylla,dwdm/seastar,kjniemi/seastar,norcimo5/seastar,avikivity/seastar,kjniemi/seastar,chunshengster/seastar,linearregression/scylla,glommer/scylla,shyamalschandra/seastar,linearregression/seastar,rentongzhang/scylla,raphaelsc/scylla,glommer/scylla,raphaelsc/seastar,slivne/seastar,bowlofstew/scylla,respu/scylla,dwdm/seastar,jonathanleang/seastar,wildinto/seastar,cloudius-systems/seastar,scylladb/scylla,tempbottle/seastar,asias/scylla,eklitzke/scylla,printedheart/seastar,victorbriz/scylla,joerg84/seastar,xtao/seastar,slivne/seastar,respu/scylla,scylladb/seastar,shaunstanislaus/scylla,ducthangho/imdb,ducthangho/imdb,rluta/scylla,mixja/seastar,joerg84/seastar,duarten/scylla,scylladb/scylla-seastar,victorbriz/scylla,gwicke/scylla,norcimo5/seastar,stamhe/seastar,dreamsxin/seastar,linearregression/scylla,aruanruan/scylla