ENH: Option to prefix dns name of clusters with the tag name.  ie master on mycluster --> mycluster-master.
    -- updates documentation and details in config
    -- optparse options
    -- add validation to check for invalid hostnames
ENH: removenode has a -f option to ignore plugin failures.  addnode and removenode have a -c option like start does
removing @ from security group prefix, adding vpc_id , subnet_id to cluster settings
using private_ip_address when connecting to a vpc node : that's what vpc is about :)
if vpc_id and subnet_id in config args the use a VPCluster otherwise go with Cluster
piping up EasyEc2 to handle vpc mainly adding vpc_id arguments
adding VPCCluster class/ Clustermanager needs to load config file at this moment
adding vpc subnet options to template
adjust security group authorization to use the connection so it works with vpc
fixing sshtomaster by adding private_ip_addr if instance is a vpc instance
adding addr attribute as i will be using this in other plugin's
check's if instance is vpc . if not uses dns_name otherwise uses
the dns_name. need to think about elastic_ip
take care of elastic ip as well
minimum required to get vpc working
some bug fixes, including one related to vpc requirement to remove @ from security_group_prefix.  @ makes this backwards incompatible...for now
make current ipcluster plugin compatible with vpc
fixes bug when volume is already attached and using vpc
linting

+ remove code redundancy
ebsimage command now compatible with vpc for instances that don't have external dns.  we should probably make a more uniform way for selecting dns/ip address
Fix Spot Request for VPC

minor whitespace fixes
remove duplication