Some small type-hints for fast next-closure implementation

to replace the explicit calls to int

Signed-off-by: Daniel Borchmann <daniel.borchmann@mailbox.tu-dresden.de>
Update depedency on jline

0.9.94 prevents «lein trampoline repl» from working

Signed-off-by: Daniel Borchmann <daniel.borchmann@mailbox.tu-dresden.de>