[vim] Set Solarized scheme after Vundle loads it

Set the Solarized colour scheme after Vundle has loaded it as a plugin,
    otherwise Vim will error saying that it can't find it.
[zsh] Alias `vi` to `vim`

On Cygin, calling `vi` does not load '.vimrc' for some reason. Alias it
to always call `vim`, which does load '.vimrc'.
[shell] Add .profile, .zprofile, ssh-agent script

Add a .profile which will read by ZSH emulating a Bourne shell.

Also adds a script to manage `ssh-agent` for systems other than Mac.