Zsh: rename .zshlocal -> .zshrc.local

This is for consistency with the already-existing .gitconfig.local, and
the soon-to-exist .hgrc.local.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Zsh: change order of override file inclusion

Let's put the .zshrc.local override last; this is really the "last
chance" opportunity to override the config that comes from the repo (as
it is anticipated that the .zsh/host/* files will be stored in the repo
if they don't contain sensitive information).

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Zsh: remove humus-specific config

I no longer access that host, so this can go away.

Signed-off-by: Wincent Colaiuta <win@wincent.com>