Update Cloudflare documentation

[killerbees19]

Important: Someone should test and review this with an old (existing) Cloudflare account/token!

It seems that the documentation for Cloudflare is outdated. There's no special privileges required to list zones.

What I've done:

1. Registered a new Cloudflare account.
2. Added a domain to my account. (Free Plan)
3. Created a new API token with only DNS:Edit.
4. Called the add/del scripts…

CF_API_TOKEN=MYSECRETTOKEN ./dns_scripts/dns_add_cloudflare test.example.net 1337
CF_API_TOKEN=MYSECRETTOKEN ./dns_scripts/dns_del_cloudflare test.example.net 1337

No error, the record will be created/deleted at Cloudflare without any problems.

[timkimber]

Thanks for updating the documentation, sorry it's taken me so long to merge it!