Fix install instructions' echo missing -e flag

Needed to expand the \n into a newline. My bad.

admin_user_path correction

Add redis-server init.d dependency - fixes #598

Force diff line to UTF-8 encoding - proper fix.

Move Unicorn unix socket out of /tmp

Fix gl-setup PATH warning when executing gl-system-install.

My git user uses bash (so .bash_profile), but I think it should work the same for sh shell.

Full warning message:

                ***** WARNING *****
gl-setup is not in your $PATH.

Since gl-setup MUST be run from the PATH (and not as src/gl-setup or such),
you must fix this before running gl-setup.  The simplest way is to add

    PATH=/home/git/bin:$PATH

to the end of your bashrc or similar file.  You can even simply run that
command manually each time you log in and want to run a gitolite command.

Run /home/git/gitolite/src/gl-system-install -h for a detailed usage message.