Only enable Perl6 folding if perl6_fold is on
Turn Perl6 folding on all the time

(for now)
Add simple folding for subs/methods
Add folds for multi/proto/only without sub keyword
Add basic fold test
Make sure we can use line continuations
Add naïve class block folding
Change fold markers to {{{/}}}
Add a bunch of tests for Perl6 folding
Remove Perl5-style prototype
Add "returns" example
Add multi/only/proto examples
Remove Perl6 fold tests under perl6/
Fix subroutine folds