drop jruby (for now).

jruby can't fork. if you were to use ichannel + jruby you'd probably
use threads and that's something i haven't tried to account for or
think about but would like to.

my main focus is making sure there are no race conditions in IPC message
passing and then I can focus on single multi-threaded processes(which safe
IPC messaging might solve for me).

dropped for now.