Fixes #71
Fixes #71

Just needed to check for nil method_id values to prevent the segfault

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