added brainfuck examples to extra-source-files
added brainfuck examples to extra-source-files

hvr/lens,danidiaz/lens,timjb/lens,omefire/lens,Gabriel439/lens,hvr/lens,cchalmers/lens,rpglover64/lens,Fuuzetsu/lens,ddssff/lens,Icelandjack/lens,cdepillabout/lens