Remove metadata.json and update application readme.
Remove metadata.json and update application readme.

* Metadata.json can be generated with the rake tasks.
* Use 'metadata[cookbook]' and 'metadata_all' to generate .json.
* Application readme needed a few more clarification points.

Shopify/chef-keepalived,wadtech/keepalived,Shopify/chef-keepalived,diegobill/keepalived,meineerde-cookbooks/keepalived,x-ion-de/keepalived,diegobill/keepalived,opscode-cookbooks/keepalived,cookbooks/oc-keepalived,opscode-cookbooks/keepalived,x-ion-de/keepalived,geidies/keepalived,jtimberman/keepalived,dnbert/keepalived,chef-cookbooks/keepalived,TAMUArch/keepalived,Youscribe/keepalived,nathwill/keepalived,cookbooks/hw-keepalived