paramiko: Update to new upstream version 1.12.1.

This release contains only minor fixes, which are:

 * Fix AttributeError bugs in known_hosts file (re)loading.
 * Note ecdsa requirement in README.

Full changelog with credits and issue IDs can be found at:

https://github.com/paramiko/paramiko/blob/master/NEWS



Signed-off-by: aszlig <aszlig@redmoonstudios.org>