Update bouncycastle to 1.50

Update bouncycastle to the latest version 1.50. And since sshd-core 0.8.0 doesn't play well with latest bouncycastle, update it as well.

I took inspiration from [this].


[this]: http://mail-archives.apache.org/mod_mbox/camel-commits/201312.mbox/%3C383957136d2d46d38de7b51ca5030eaf@git.apache.org%3E