- Fix for wrong value of removeKeyOnExit being passed to
  LoginProcess.__init__
Trying to fix issue where temporary key wasn't getting removed
from agent when running in "password" mode.  There were a
few different bugs contributing to this.  One was that
removeKeyOnAgent wasn't being properly set in launcher.py
when creating the LoginProcess object, which was fixed in the
last commit.

A second issue (being fixed in this commit), is
that calling KeyDist's shutdown() from LoginProcess's
shutdownReal() wasn't calling KeyDist's shutdownReal(),
so now LoginProcess's shutdownReal() calls KeyDist's shutdownReal()
directly, instead calling KeyDist's shutdown() method.

A third issue (not fixed yet) is that the temporary key being
generated seems to be missing its comment (as created with
ssh-keygen -C), so the KeyModel method which tries to remove
the key from the agent doesn't find any key with "Launcher"
in its comment. (Other methods of removing a key from the
agent using the private key would require entering a passphrase.)
Updating submodule version.