Update README.md

Updated cf CLI version and index.php in root directory
Update README.md

Added link to cf v6 installation instructions.
Merge pull request #2 from DanielBerman/master

Updated instructions following Pivotal feedback
ZCLOUD-178 Generate random admin password instead setting default password to changeme
ZCLOUD-173 Replace 403 error page with our custom one.
Update README.md

New password instructions, and push command
Merge pull request #3 from DanielBerman/master

Update README.md
Merge branch 'master' into zendtech-master/master