Fix backtraces
Fix backtraces

I think this is the most correct way of discarding frames generated
after returning from byebug's processing and giving back control to the
user.

yui-knk/byebug,yui-knk/byebug,guilherme/byebug,yui-knk/byebug,k0kubun/byebug,deivid-rodriguez/byebug,webdev1001/byebug,guilherme/byebug,webdev1001/byebug,os97673/byebug,os97673/byebug,scalp42/byebug,deivid-rodriguez/byebug,davidmowrer/in_class_projects_t2,ozydingo/byebug,davidmowrer/in_class_projects_t2,miamiruby/byebug,edward/byebug,icebreaker/byebug,ozydingo/byebug,davidmowrer/in_class_projects_t2,scalp42/byebug,icebreaker/byebug,deivid-rodriguez/byebug,saisai/byebug,miamiruby/byebug,guilherme/byebug,edward/byebug,k0kubun/byebug,saisai/byebug,k0kubun/byebug