contributing: shorten github issue template
contributing: shorten github issue template

euank/rkt,lucasallan/rkt,markllama/rkt,cab105/rkt,matthaias/rkt,squeed/rkt,Wilybald/rkt,lucasallan/rkt,coreos/rkt,akshaykarle/rkt,tmrts/rkt,shobhit85/rkt,sstabellini/rkt,coreos/rkt,euank/rkt,squeed/rkt,kinvolk/rkt,shobhit85/rkt,sstabellini/rkt,yifan-gu/rkt,Wilybald/rkt,matthaias/rkt,mike1729/rkt,rkt/rkt,rkt/rkt,Shashwatsh/rkt,mike1729/rkt,Shashwatsh/rkt,kinvolk/rkt,s-urbaniak/rkt,achanda/rkt,alban/rkt,alban/rkt,lucasallan/rkt,intelsdi-x/rkt,markllama/rkt,nhlfr/rkt,sgotti/rkt,jakon89/rkt,joshix/rkt,dgonyeo/rkt,ybubnov/rkt,dgonyeo/rkt,yifan-gu/rocket,ybubnov/rkt,jonboulle/rkt,monstermunchkin/rkt,sstabellini/rkt,sgotti/rkt,cab105/rkt,jjlakis/rkt,dgonyeo/rkt,coreos/rkt,mike1729/rkt,achanda/rkt,jjlakis/rkt,yifan-gu/rkt,s-urbaniak/rkt,jakon89/rkt,lucasallan/rkt,shobhit85/rkt,rkt/rkt,tmrts/rkt,monstermunchkin/rkt,akshaykarle/rkt,rkt/rkt,akshaykarle/rkt,sgotti/rkt,tmrts/rkt,yifan-gu/rocket,squeed/rkt,kinvolk/rkt,markllama/rkt,joshix/rkt,jonboulle/rkt,monstermunchkin/rkt,Wilybald/rkt,kinvolk/rkt,euank/rkt,joshix/rkt,alban/rkt,Wilybald/rkt,cab105/rkt,jakon89/rkt,intelsdi-x/rkt,nhlfr/rkt,s-urbaniak/rkt,yifan-gu/rocket,jjlakis/rkt,jonboulle/rkt,joshix/rkt,nhlfr/rkt,ybubnov/rkt,achanda/rkt,matthaias/rkt,Shashwatsh/rkt,yifan-gu/rkt,intelsdi-x/rkt